Ricardo Tutorial

ShowSI Tutorial, Phase 1 - Building a Single Cylinder Model Step 1 - Starting WaveBuild, Setting General Parameters, and Creating a Simulation Title In this step we will open WaveBuild and establish some preliminary settings that are important for every simulation. Chapter sections 1.1 Starting WaveBuild 1.2 Setting General Parameters 1.3 Creating a Simulation Title Example Input File: .\examples\engine\TUT_si\tut_si1.wvm Example Output File: .\examples\engine\TUT_si\tut_si1.wps 1.1 Starting WaveBuild Open the WaveBuild GUI by following these steps: Windows:  From the Start menu select Programs > Ricardo > WAVE > WaveBuild 8.0 Linux/UNIX:  Type wb at the command prompt Once the application opens, the WaveBuild GUI should have a blank canvas and appear as in Figure 1. Figure 1: WaveBuild window at startup The title bar is across the top of the WaveBuild GUI window. It lists the name of the currently open file (NoName.wvm by default, until renamed). If changes have been made to the file and haven't yet been saved, an asterisk (*) will appear next to the filename. See Figures 2 and 3. Figure 2: Title bar when WaveBuild application first opens Figure 3: Title bar with unsaved changes to the model The pull-down menus are listed across the top of the GUI, beneath the title bar (see Figure 4). Clicking these with the left mouse button will open up menus with selection items. Linux/UNIX users: The Help pull-down menu will appear at the far right side of the window. Figure 4: Pull-down menu The toolbar contains shortcut buttons for frequently performed operations. New Executes the File > New... function. Open Executes the File > Open... function. Save Executes the File > Save function. Undo Executes the Edit > Undo function. Redo Executes the Edit > Redo function. Find Executes the Edit > Find function. Select Puts the cursor in select mode. Place Element Puts the cursor in element placement mode, which places an instance of the element selected in the Elements Tab for every mouse click on the canvas. Cut Executes the Edit > Cut function. Copy Executes the Edit > Copy function. Paste Executes the Edit > Paste function. Constants Table Executes the Simulation > Constants > Table function. Run Input Check Executes the Run > WAVE > Input Check function. Run Screen Mode Executes the Run > WAVE > Screen Mode function. Run Batch Mode Executes the Run > WAVE > Batch Mode function. WavePost Executes the Run > WavePost function. 1. The text field tells you exactly which case you are in and how many cases there are in total. Figure 6: How to Edit the Canvas Properties Figure 5: The WaveBuild canvas The Case Manager is at the bottom of the canvas. the background of the text field turns red as a reminder that you are not in Case 1. You can type directly into the text field and press enter to jump to a specific case.WNOISE Executes the Run > WNOISE function. Switch back to Case 1 if you wish to make any changes to the model geometry. The canvas is the main portion of the WaveBuild window and where the flow network will be assembled and described (see Figure 5). and grid appearance. By default. Text Editor Opens the Text Editor specified in the Tools > Options tab. the checkbox is checked for all new cases. previous case . annotation display.. next case .. The canvas is a customizable surface. Favorite Application Opens the Favorite Application specified in the Tools > Options tab..2 Setting General Parameters . The Run checkbox allows you to select whether or not WAVE should execute the current case in the simulation. You can customize the properties for the WaveBuild canvas by selecting the Canvas Properties. context menu item.. The and buttons allow you to the add and delete cases while the arrow buttons allow you to navigate between existing cases (first case . Customizable options include canvas size. option from the Edit pull-down menu or by right-clicking on the canvas background and selecting the Edit Canvas Properties. last case ). In any case other than Case 1. use the file browser button to open a file browsing window and select the properties file to use. Once we place the engine cylinders on the canvas. For this tutorial. This is because the units are listed as s for seconds and 30 seconds far exceeds the recommended value for simulation duration in the intelligent defaults settings.With any new model. This option is turned off by default because in most instances the final conditions for a converged case are closer to the final conditions of the following case than the user-imposed initial conditions. the first step should always be to define the general parameters for the simulation. velocities. denoting a filename. and species concentrations in every subsequent case when multiple cases are defined (Case #1 is unaffected by this setting). etc. This will fill the text field with an absolute file reference. the user can change the units for entry. click on the file tag button to open the Fuel Property Tag Selector and double-click on INDOLENE (see Figure 7). typing in the word directly into the field indicates the use of a tag. by its nature. and Liquid Fuel. using pointed brackets. numbered Species 1 to 5 respectively. simulates fluid flow using a timebase of seconds. specifically the units system to initialize all data entry. Since we don't know how many cycles our simulation will take to converge. Burned Fuel. but user entry fields are changed to cycles for convenience. the toggle button should remain off. gas temperatures. Changing the selection in this option menu at a later point will not convert previously-entered values between units systems! Under the Start Options section of the panel. This will automatically fill in the word INDOLENE in the text field. Select SI [mm] from the Units option menu. pressures. each case will converge to the final solution quicker. Assuming this is true.. we will set a typical number for a gasoline engine and note the convergence behavior at run time. under the Simulation pull-down menu. Similarly. Wherever an input is required in WaveBuild. Open the General Parameters Panel by selecting General Parameters. Under the Fuel and Air Properties section of the panel. Note that the background of the Simulation Duration field turns yellow. When a cyclic process is introduced to the simulation (such as an engine cylinder. all units will be defined in the SI system with mm as the basic unit of length. this units field will automatically change to cycles and the background of the text field will change to white. Vaporized Fuel. pressures.. an oscillating flow source. For this tutorial. In the General Parameters section of the panel. type 30 in the Simulation Duration text field. If our number is higher than required. Turning this on will cause WAVE to start from the user-imposed initial conditions for wall temperatures.) WaveBuild knows to change to a cyclic timebase. <>. auto-convergence will stop the simulation. note the toggle button next to Reinitialize Flowfield Between Cases. and . five species are used and transported throughout the model. WAVE. the units for that input will be displayed next to the entry field. "Behind the scenes" the WAVE solver will still be solving everything in a seconds timebase. When a numeric input is provided. to surround the entry. All properties for these species are defined in a single properties file (with a . These are Fresh Air. if it is in another unit than the initialized unit. Figure 7: Selecting the INDOLENE tag In WAVE. Burned Air. We will be simulating an engine and this number will define the number of engine cycles to simulate. To specify a particular file not aliased in the tags file.fue extension) that contains information on how the fuel and air react at different temperatures. PID controller tolerances are also included in the convergence calculation. a crank angle can be specified and should be just after the latest IVC for cylinder #1 in the simulation. By default (setting of auto). For this tutorial. the calculated wall temperature (T) is also checked for convergence. Ricardo ships numerous pre-made properties files and all are selectable from the default tags list. The user can create their own file if desired by clicking on the Create Properties File button to use the pre-processor. WAVE uses the IVC of cylinder #1 as the end of cycle. Note the End of Cycle Angle text field. The appropriate properties file should be selected for the fuel being used in the model. This is acceptable for almost all engine simulations except when VVT is employed and continuity between cases is important. This field is used to specify the crank angle that WAVE will use to denote the start/end of subsequent engine cycles. For simulations using only air. Finally. For all simulations. velocity (U) and pressure (P) are checked for convergence in every computational cell in the last timestep of each cycle. In that case. the user has the option of adding any cycle-averaged quantities desired to be included as additional criteria. When finished. the default setting of auto is appropriate. which tells WAVE to end the simulation if it converges to within the specified tolerance value for the specified number of consecutive cycles (default of 1% for 1 cycle) regardless of whether or not it has reached the specified duration. the General Parameters should appear as in Figure 8. Turning this option off will cause WAVE to run to the full specified duration for each case in the simulation. In simulations where WAVE's structural conduction model is implemented. This tab allows the user to activate the auto-convergence mechanism. In simulations where WAVE's control systems are used. . Figure 8: Completed General Parameters Panel Click on the Convergence tab. any properties file may be specified since all contain information on the properties of air.concentrations. Type SI Tutorial. It can be up to 120 characters long and may include any alphanumeric characters or symbols with the exception of curly brackets.For this tutorial..$case. This title will be printed to the output file by WAVE at runtime so it is convenient to give the model a descriptive name for later reference.. $fullcase. below. Figure 9: Convergence Tab Press the OK button to close the General Parameters Panel and save the settings. $version.3 Creating a Simulation Title Add a Title to the file by selecting Title. the toggle button should remain on and the default values are acceptable. . the WaveBuild canvas should appear as in Figure 10. Constants (discussed in Step 4 of this tutorial) and operations on constants may be used and will be evaluated when placed inside curly brackets. { }. When finished. from the Simulation pull-down menu. Pre-defined WAVE constants are convenient to use sometimes and include $file. Also useful are user-defined constants that control important parameters such as engine speed and load. When finished. 1. The simulation title appears centered across the top of the WaveBuild canvas and is fixed in this location. and $date. the Convergence tab should appear as in Figure 9. $subcase. The Title Panel will pop up for you to enter a text string that will serve as the simulation title. { }. 4Cylinder Gasoline Engine at {SPEED} rpm in the Title text field and click on the OK button to apply the title (the constant SPEED will be defined in Step 4). To save the file elsewhere or with a different name.Figure 10: WaveBuild canvas with Simulation Title Save your model Click on the Save button in the toolbar to save the file. for "WAVE model"). you will be prompted for a filename and directory where the file will be written (the file is saved with a .. or if the file is not a newly created file (opened from a pre-existing file).. . You will also be prompted to add comments for the file (this option can be deactivated via the File tab on the Options Panel located under the Tools. the currently open file will be overwritten. Save this file with a descriptive name. Proceed to Step 2 .. When the save button is subsequently clicked. The first time the file is saved. option from the File pull-down menu.wvm.Building a Single Cylinder Model Step 2 .wvm extension. Phase 1 . such as tut_si1.Building the Flow Network on the WaveBuild Canvas In this step we will layout the junction and duct entities that are required for the single cylinder model on the WaveBuild canvas.Building the Flow Network on the WaveBuild Canvas Show SI Tutorial.. select the Save As. pull-down menu). Hold down the left mouse button and drag it onto the WaveBuild Canvas.Chapter sections Example Input File: .1 Placing Required Junctions The basic geometry of the system we will model in this phase is shown in Figure 1. The mouse pointer changes to a "+" sign when the mouse is moved over the WaveBuild canvas. a junction of the selected type will be placed on the canvas every time you press any mouse button. click on the place element + button in the toolbar across the top of the WaveBuild GUI. one for the tapered section and one for the un-tapered section. The mouse will remain in junction placement mode until you click on the Select button on the toolbar across the top of the WaveBuild GUI or hit the Esc key to return to select mode. Figure 1: Single Cylinder Layout Sketch Move the mouse over the Ambient junction icon listed in the Elements Tree.wps 2. The mouse pointer is now in junction placement mode. In order to model this.2 Connecting the Junctions with Ducts Example Output File: . dropping it anywhere. To place additional junctions without continually dragging and dropping.wvm 2.\examples\engine\TUT_si\tut_si1. This will place one junction of the simple ambient type onto the model canvas (see the WaveBuild HELP on how to work with the Elements Tab). The open ends of the ports will be represented using standard ambient elements. In junction placement mode. at which point the mouse pointer will return to appearing as an arrow when moved over the canvas. . We will use simple orifice elements to connect the two ducts (one orifice on each side of the cylinder).1 Placing Required Junctions 2. we will have to represent both the intake port and exhaust port using two duct elements.\examples\engine\TUT_si\tut_si1. Proceed to Step 3 . The leftmost ambient will be the intake ambient and the rightmost will be the exhaust ambient.Defining Ambients. it is merely a coincidence in this case!). junctions "snap" to the nearest grid intersection point.e.wvm_bak1. This is an indication that some geometric property of the ducts (i. WaveBuild will create up to 9 backup files with the . as you connect the two ports of an orifice junction. the orifice icon will "automagically" appear again and the ducts will turn black! Figure 3: Ducts connecting Junctions on Canvas Save your model Click on the Save button in the toolbar to save the file. the Left to Right convention doesn't necessarily mean Left to Right on the screen. all of which can be opened and viewed using WaveBuild. labeled orif1 in Figure 2. When finished the WaveBuild canvas should appear as in Figure 2. This behavior can be modified via the Edit > Canvas Properties. Connect the remaining junctions following the Left to Right convention (remember. menu item. This draws/creates a duct between the two junctions. Ducts. drag and drop an Engine Cylinder element from the Elements Tree between the Orifice junctions. click and drag from the pink connection point on the leftmost ambient junction. ducts must be created to connect the junctions together. The orifice icon dynamically adjusts its appearance to reflect any step change in duct diameters. Also.2 Connecting the Junctions with Ducts Now that all of the junctions required for the single cylinder model have been placed on the canvas.wvm file with the new information and backs up the previous . to the left connection point on the neighboring orifice junction.wvm file to a file with the extension . NOTE: The ducts connecting the junctions appear as yellow lines. Drag and drop two Orifice elements from the Elements Tree on the canvas between the ambient junctions. and Orifices . the canvas should appear as in Figure 3. diameter) has not been properly defined. This overwrites the . Finally.. Figure 2: Junctions placed on the canvas 2. Using the left mouse button.Place two of the Ambient junctions on the canvas approximately 12 grid squares apart horizontally. When finished. After you enter the duct properties in Step 3. Note that when placed on the canvas.bak extension.. labeled amb1 in Figure 2. the icon of the orifice disappears because the ducts connected on both sides have default diameter values of 0 (zero) at this point. The Acoustic End Correction is only used for acoustic simulations and is discussed in detail in the Acoustics Manual. The Diameter field has a default value of AUTO to assume the same diameter as the attached duct (no restriction created). The default setting of Floating is appropriate in almost all cases and should not be changed. Discharge Coefficient. such as an engine operating at high altitude.\examples\engine\TUT_si\tut_si1. This is only applied to flow going from the Ambient into the attached duct and should be a value between 0 and 1 if specified. The Diameter. below. or is not at sea level.3 Defining Orifices Example Input File: .\examples\engine\TUT_si\tut_si1.wvm Example Output File: .1 Defining Ambients 3. however a value of 0 (zero) makes the ambient junction behave like a closed end to the attached duct (an end-cap).Show SI Tutorial. like the outlet of a compressor or inlet of a turbine. Chapter sections 3. the default values are all appropriate and we only need to change the name of the junction.Defining Ambients. Temperature. Phase 1 . and Acoustic End Correction fields are used to model the orifice created where the duct ends at the ambient.1 Defining Ambients With the general parameters defined (specifically a units system) and all of the relevant ducts and junctions placed on the canvas. Ducts. . The selection of Fixed or Floating Solution Type is discussed in detail in the Acoustics tutorials. The ambient's diameter value can never be larger than the diameter of the attached duct as it would have no physical meaning.Building a Single Cylinder Model Step 3 . For this simulation. Do the same for the right-most ambient junction and type Exhaust in the ID text field. the Ambient Panel should appear as in Figure 1. Double-click with the left mouse button on the left-most ambient junction. When finished. and Orifices In this step we will select all of the elements (ducts and junctions) on the WaveBuild canvas.wps 3. the user can specify the conditions of the ambient atmosphere (Pressure. and define their geometric values and initial/boundary conditions. Temperature and Pressure fields on the Ambient tab and all inputs on the Initial Fluid Composition tab are used to specify the fluid conditions of the atmosphere around the attached duct. In some simulations. The Discharge Coefficient can be set to AUTO to have WAVE calculate this value internally during the simulation. The default values of 1. and Species Concentrations) as well as specify the properties of the orifice at the end of the attached duct. it is time to define the geometric characteristics of the model as well as specify the initial conditions and boundary conditions. This will open the Ambient Panel. the left-most Ambient junction will be the intake ambient. We will start by defining the Ambient junctions. the user may choose to dramatically change the temperature and pressure and/or adjust the composition to model a boundary that is either not atmospheric. Type Intake in the ID text field (name for the junction as displayed on the canvas and in the output files).0 [bar] and 300[K] and a composition of 100% fresh air are suitable for this simulation and don't need to be changed.2 Defining Ducts 3. As stated earlier. In the Ambient Panel. Across the top of the Duct Panel is the Duct ID (name for the duct as displayed on the canvas and in the output files) and. Figure 2: Single Cylinder Layout Sketch Double-click with the left mouse button on the duct labeled duct1 to open the Duct Panel. Assume that all the geometric data for the system has been measured and recorded and that a labeled sketch is provided as in Figure 2. a duct is defined by Left and Right Diameters.Length.Figure 1: The Ambient Panel for the Intake 3. . Discretization. and Initial Conditions. Minimally.2 Defining Ducts Next we will define the ducts. the junctions connected to the duct's Left and Right ends are listed. in the Connectivity section. the Dimensions tab. The bottom of the Duct Panel is reserved for two layers of tabs which hold entry fields in which the user will specify all information relevant to that duct. Under the top level tab of Duct Data.1 [mm] so. The engine bore for this example is 78.The middle of the Duct Panel is the Schematic section which will update the drawing of the duct to reflect the entered geometric dimensions (Bend Angle is not drawn in the schematic as it has no physical meaning in a 1-D model. Fuel Injectors. it is simply used to calculate a pressure loss based on the angle and bend radius). Of all of those tabs. Spray Impingement Points. set the Discretization Length to 35 [mm] (click here to read a sidebar on Discretization). and Thermocouples will also appear in the schematic if present in the duct. type the dimensions given for duct1 in Figure 2 into the appropriate entry fields (Left and Right Diameters and Overall Length). theDimensions tab for duct1 should appear as in Figure 4. When completed. Figure 4: Duct Panel Dimensions Tab for duct1 . there are three of primary importance that we will use in this tutorial. with the Shape selected as Circular. the Coefficients tab. following the general recommendation for discretizing the model for performance simulation. and the Initial Conditions tab are particularly relevant in all ducts and are the only tabs we will be editing during the course of this tutorial (see Figure 3). Figure 3: Required Duct Data Tabs On the Dimensions tab. 0 imply that twice the standard pressure loss due to friction and twice the standard heat transfer is occurring.0.0. The Left and Right end Discharge Coefficients will be automatically calculated by WAVE when left as auto based on the diameter of the duct at the relevant end and the diameter of the neighboring duct/orifice.5 in the Heat Transfer coefficient fields under the Coefficients section of the tab (click here to read a sidebar on Port Flow Testing to understand why).0 for the Pressure Loss Coefficient is suitable for this simulation. Keep in mind that surface roughness will affect BOTH of these parameters and that pressure loss due to increased heat transfer can be much greater (expansion/contraction of the gas) than pressure loss due to friction! Figure 5: Duct Panel Coefficients Tab for duct1 On the Initial Conditions tab.  Note that the Friction and Heat Transfer Coefficients have default values of 1. The initial conditions as set will be flushed out within the first few engine cycles of the simulation. These values are multipliers for the standard calculation. type 0 (zero) in the Friction and 1. this can be overridden by typing in a value for the Discharge Coefficient from 0. When finished. Temperature. the Initial Conditions tab should appear as in Figure 6. These multipliers may be used as "tuning knobs" to adjust friction and heat transfer and should be changed according to the surface roughness of the material and flow conditions in the duct. If desired. Thus values of 0.0 [bar] and 300 [K] are appropriate for most engine . When finished. Default settings of 1. all of the default settings are correct for our model.0 imply that there is no pressure loss due to friction and no heat transfer occurring along the length of the duct while values of 2. the Coefficients tab should appear as in Figure 5. In the case of duct1. the default value of auto is suitable and should not be changed. The default setting of 0. type the conditions given for duct1 in Figure 2 into the appropriate entry fields (Pressure.On the Coefficients tab. For the purpose of this tutorial.0 to 1.  Note that initial conditions of Pressure and Temperature need not be extremely accurate in an engine simulation as the gas will quickly move through the system and conditions will be recalculated frequently. and Wall Temperature). the Structural Conduction model should be activated and the wall temperature will be calculated during the simulation to give reasonable results. Turbo/Supercharged simulations should have more appropriately set conditions to reflect the "boosted" state of the fluid and avoid start-up calculation errors. edit duct1 to have a Right Diameter of 50 [mm]. not only is the Wall Temperature value as entered the initial Wall Temperature.5 for each duct and do not enter Bend Angles for duct2 and duct3! Figure 6: Duct Panel Initial Conditions Tab for duct1 3. and duct4 and enter the relevant information according to the schematic shown in Figure 2. special attention should be paid to setting Wall Temperatures throughout the model to ensure that heat transfer is accounted for appropriately. If reliable wall temperature data is not available. Click the OK button to close the Duct Panel for duct1.3 Defining Orifices When all of the ducts have been defined. smooth line across both the top and bottom. the junctions appear with a straight. As above. it is also the fixed Wall Temperature for the duration of the simulation! Thus. Make sure to set the Friction coefficient to 0 (zero) and the Heat Transfer coefficient to 1. edit duct2. especially in the exhaust system. To demonstrate the altering appearance of the orifice junction. Note the orifice junction changes in appearance to illustrate the step change from a larger to a smaller diameter duct.simulations. note on the WaveBuild canvas that the orifice junctions have reappeared. Since the ducts all have matching diameters at the ends where they are joined by orifice junctions. duct3.  Note that if the Structural Conduction model (discussed in later tutorials) is not active for a duct. Use a Discretization length of 35 [mm] on the intake and 40 [mm] on the exhaust. . Figure 7: Completed WaveBuild Canvas Save your model Click on the Save button in the toolbar to save the file. If a restriction is to be modeled. a Diameter smaller than the smallest of the two attached ducts should be used. Click the Undo button in the toolbar to return the Junction Diameter to auto again. Now double-click on the orif1 junction and note the only editable fields for an orifice junction are the ID of that junction and the junction Diameter (diameter of the orifice plate) if one exists. than the default setting of auto is sufficient. Type 20 [mm] in the Diameter text field and hit the OK button.Defining the Engine . For this tutorial all orifice junctions will have a Diameter of auto unless otherwise specified. the WaveBuild canvas should appear as in Figure 7. Proceed to Step 4 . The auto setting implies that the diameter of the orifice is equal to that of the smaller of the two attached ducts.Click the Undo button in the toolbar to return the Right Diameter of duct1 to 35 [mm] again. Note the orif1 junction now appears as if an orifice plate is reducing the diameter at the junction. When completed. Orifice with no change of area Orifice with contraction Orifice with restriction An orifice diameter can never be larger than the diameter of the smallest attached duct as it would have no physical meaning. If an orifice junction is simply used to join two duct ends together. however a value of 0 (zero) makes the junction behave like a closed seal between the attached ducts. 2 The Operating Parameters Tab 4. Heat Transfer.1 The Geometry Tab To define the engine. .wvm Example Output File: .0\examples\engine\TUT_si\tut_si1. These are Geometry.0\examples\engine\TUT_si\tut_si1. Operating Parameters.Defining the Engine In this step we will input all of the required data for the engine.\Ricardo\WAVE\8. There are four primary tabs that are important for every engine. and Combustion. It physically would consist of all engine cylinders represented on the WaveBuild canvas (currently only one) but also includes physical sub-models for combustion.Building a Single Cylinder Model Step 4 ..\Ricardo\WAVE\8. heat transfer. The Engine currently is not an entity on the canvas. from the Model pulldown menu. Phase 1 .4 The Combustion Tab 4.Show SI Tutorial.3 The Heat Transfer Tab Example Input File: . open the Engine General Panel by selecting Engine. each used to define the characteristics of the engine or the physical sub-models associated with the engine.. Chapter sections 4. friction.wps 4. etc. The Engine General Panel consists of numerous tabs.1 The Geometry Tab 4. If the simulation is only to simulate tested speed/load points.005 CCF 400 [Pa/min*m] QCF 0.0 2 [mm] Clearance Height Table 1: Data to be entered in the Configuration fields ACF 0. The equation to calculate FMEP in WAVE is: No. The No.On the Geometry tab. no combustion via cancelling all injection events).35 [bar] BCF 0. the FMEP can be entered directly using only the ACF value (directly entering FMEP in the appropriate pressure units) and setting the other coefficients to 0 (zero). under the Friction Correlation section enter the relevant data for this engine as shown in Table 2. When data is collected in the test cell.1 [mm] Stroke 82. This model is used to calculate the FMEP (Friction Mean Effective Pressure) for the engine. The Strokes per Cycle field is used to define the engine as a 2-stroke or 4-stroke engine (optionally a 6. The user must enter the correct number of engine cylinders manually. When completed.2 [Pa/min2*m2] Table 2: Data to be entered in the Friction Correlation fields FMEP = ACF + BCF(Pmax) + CCF(rpm * stroke/2) + QCF(rpm * stroke/2)2 The use of the BCF term is to account for changes in Pmax. . which can be used to vary frictional losses across a range of engine loads.0 [mm] Connecting Rod Length Wrist Pin Offset Compression Ratio 150.0 [mm] 10. The Motored option allows for engine motoring simulation (engine pumping only. the Geometry tab should appear as in Figure 1.or 8stroke engine for research purposes). varying frictional losses across a range of engine speeds. The Engine Type field is used to enable different combustion and emission models when either SI or Diesel are selected. it can be plotted and correlated using the Chen-Flynn model so that FMEP may be calculated at non-tested engine speed/load conditions. The CCF and QCF terms are used to account for changes in rpm.0 [mm] 0. These coefficients are used in the Chen-Flynn friction correlation model. of Cylinders field does not automatically update when cylinders are placed on the screen (this allows for definition of the engine before the model is built). of Cylinders 1 Strokes per Cycle 4 Engine Type Spark Ignition Bore 78. under the Configuration section enter the relevant data for this engine as shown in Table 1. On the Geometry tab. open the Constants Panel by clicking on the Constants Panel button in the toolbar or by selecting Simulation > Constants > Table.. This will correspond to the {SPEED} value used in the Engine General Panel for Engine Speed in rpm. In the Engine Speed text field. enter {SPEED} to denote the use of the SPEED constant (also used in the Simulation Title in Step 1). Figure 2: The Operating Parameters tab . This will allow the simulated engine speed to change between cases once we add more cases in Phase 3 of the tutorial. stating that the constant {SPEED} is undefined (Figure 2). from the pull-down menu. Note that the background of the text entry field turns yellow. set a value of 6000. Hover over the text {SPEED} and note the tooltip that pops up. This is to warn the user that the value is outside of the generally acceptable range of values for the Engine Speed field. Click OK to close the Constants Panel and save the setting. the Constants Panel should appear as in Figure 3. No constants have yet been defined so the Constants Panel should be blank. Type SPEED under the Name column and under the Case 1 column.Figure 1: The Engine General Panel Geometry tab 4. When completed. To define this constant..2 The Operating Parameters Tab Click the Operating Parameters tab to bring it to the front. the Operating Parameters tab should appear as in Figure 4. and piston face areas exposed to the combustion chamber. Since the piston face and cylinder head are not usually flat slabs of metal. and the added input on this tab for clearance height. connecting rod length. there is a Surface Area Multiplier included for each to account for domed heads. Hover the mouse over the Engine Speed entry in the text field to pop up the tool tip and note that the constant is now being evaluated correctly as in Figure 4. Also note that the simulation title at the top of the WaveBuild canvas has updated to reflect the value of the SPEED constant as given in the title. The area of each is simply calculated from the provided geometry for bore. Figure 4: The Operating Parameters tab with SPEED defined 4.3 The Heat Transfer Tab Click the Heat Transfer tab to bring it to the front. there is only one type of heat transfer model available -. For the standard engine cylinder.0 [bar] and 298 [K] respectively. The Reference Pressure and Reference Temperature fields can be left as their default values of 1. piston bowls. etc. stroke. These values are used in the calculation of volumetric efficiency for the engine and may or may not correspond to the ambient conditions of the dynamometer cell when tests are performed (different companies use different practices).Figure 3: The Constants Panel Once the SPEED constant has been defined. Multipliers are also provided to increase/decrease total heat transfer when the intake valves are open (heating of intake charge affects Volumetric . When completed.the Woschni correlative model for convective heat transfer (1967). the background of the Engine Speed text entry field should turn white to denote an acceptable value. This model assumes simple heat transfer from a confined volume surrounded on all sides by walls representing the cylinder head. cylinder liner. 0 Piston Top Surface Area Multiplier Cylinder Head Surface Area Multiplier 1. Modifications to the standard Woschni model have been added to compensate for varying levels of IMEP. enter the relevant data for this engine as shown in Table 3. For the purpose of this tutorial.0 Table 3: Data to be entered in the Heat Transfer Tab When completed.Efficiency) and when the intake valves are closed (during compression/combustion/exhaust). This can be selected by changing the Woschni Model from Original (1967) to Load Compensating (1990). Woschni Model Original Heat Transfer when Intake Valves are Open 1. Adding swirl will increase the total heat transfer due to increased charge motion in the cylinder. .6 (to make 7665 mm2) Piston Top Temperature 520 [K] Cylinder Head Temperature 520 [K] Cylinder Liner Temperature 400 [K] Intake Valve Temperature 420 [K] Exhaust Valve Temperature 480 [K] Swirl Ratio 0.0 (flat-top piston) 1.0 Heat Transfer when Intake Valves are Closed 1. the Heat Transfer tab should appear as in Figure 5. Select the SI Wiebe option from the Combustion Model drop-down menu. time. The SI Wiebe model is very commonly used and represents experimentally observed combustion heat release quite well for most situations. we have two combustion models available to use -. This panel separates the Primary Model choice (required) from the Secondary Model choice (optional.0 [deg] for the Combustion Duration (10-90%). 2. The first derivative of this function is the rate of heat release. however. Click the OK button to save the settings for the Engine General Panel and close it.0 [deg] for the Location of 50% Burn Point and 31. This data can be directly entered into WAVE as a table with a combustion start time and efficiency.Figure 5: The Engine General Panel Heat Transfer tab 4.0 is an appropriate value and should be used. Watch the plot actively update as these values are entered. the SI Wiebe model simply uses an S-curve function that represents the cumulative heat-release in the cylinder. Fraction of Charge to Burn should be left at the default value of 1. Since we are modeling a spark ignition engine and selected the Spark Ignition option on the Geometry tab. The default value of 2. click the Combustion tab to bring it to the front. Change it and watch the shape of the burn curve change as well. For this example.4 The Combustion Tab Finally. When completed. The general engine cylinder in WAVE simplifies combustion. It does not use a predictive combustion model but simply models the heat release caused by combustion vs. Enter 8. More widely used. Crank Angle data is available directly for every speed/load point to be tested by the model. layered on top of the Primary Model) and Emissions Models.0 as well.0 for the Exponent in Wiebe Function is appropriate for most cases.the SI Wiebe and Profile models. The Profile model is used when Heat Release vs. . the Combustion tab should appear as in Figure 6. 3 Defining the Exhaust Valve . Chapter sections Example Input File: 5.2 Defining Coefficients (Flow vs.\examples\engine\TUT_si\tut_si1.wvm Example Output File: .\examples\engine\TUT_si\tut_si1.Defining the Intake and Exhaust Valves In this step we will define the intake and exhaust valves by specifying their lift behavior and flow restriction behavior. Discharge) 5.wps 5.Defining the Intake and Exhaust Valves Show SI Tutorial.1 Defining the Intake Valve Lift Behavior . Proceed to Step 5 .Building a Single Cylinder Model Step 5 .Figure 6: The Engine General Panel Combustion tab Save your model Click on the Save button in the toolbar to save the file. Phase 1 .1 Defining the Intake Valve Lift Behavior 5. etc. Anywhere a valve is present (on an engine cylinder. Click the OK button to accept the Lift type and the Lift Valve Editor will automatically appear.. Figure 1: Adding Valve Connections via the Cylinder Panel To define a valve. it is clear that no valves have yet been defined.. WaveBuild places engine cylinders on the screen with two connections by default. As it is blank. It assumes that the first connection to be used is an intake valve and the second connection to be used is an exhaust valve. for use anywhere in the model. For this tutorial.) the user must tell WAVE which globally defined valve to use. Any other valves created (by double-clicking on the cylinder junction and editing the Number of Valves field to be larger than 2) are assumed to be intake valves. Click on the Add button to create a new valve. select Valves. The blue connection point to duct2 denotes an intake valve and the red connection point to duct3 denotes an exhaust valve. The Valve List panel will pop up. the two valves created by default are suitable and the number of valves should not be changed. for example. allows the user to define an intake valve once and then use it for all engine cylinders. This is correct for this model but is purely coincidental. selected by default). This intake/exhaust status can be changed by highlighting the connection of choice and changing the Type in the drop-down menu (see Figure 1 for example of a modified Cylinder Panel). Valves are defined globally. in a valve-specific junction. from the Model pull-down menu. . This. The standard valve on an engine cylinder is a Lift valve. This will pop up the Add Valve Panel where the user selects which type of valve to use.The connections from duct2 and duct3 to the cyl1 junction are assumed to be valves (all engine cylinder connections are assumed to be valves). The first entry field under the Valve Parameters section of the panel is the Reference Diameter. type in a Reference Diameter of 35 [mm]. right). it need not be entered. whatever diameter was used to non-dimensionalize the data should be entered here. The Heat Transfer Diameter is only required if the valve is an engine valve and the engine conduction submodel is activated – for this tutorial. Figure 2: Valve Measurements typically used . For this tutorial. This value is typically the inner-seat diameter (see Figure 2. but if the portcoefficient data has been provided in nondimensionalized format. 0 1. There are numerous options for entering this data including:  Manually entering data into the array  Copying and Pasting an array from MS Excel (on PC platform)  Reading in a pre-formatted external file  Using a tag to alias a pre-formatted external file INTAKE VALVE Diameter Lift Profile 35 [mm] SI1INT tag Cycle Anchor 330 deg Profile Anchor 0 [deg] Duration Multiplier Lift Multiplier Lash Rocker Ratio Angle Type Coefficient Profile 1.414 0 1. time (time is entered as cam or crank angle degrees). In the Valve Lift Profile Editor.Click on the Edit Lift Profile button to open the Valve Lift Profile Editor. This behavior is described as the lift of the valve vs.0 Crank CFTYP tag . data must be entered for the behavior of the valve. For this tutorial the data has already been provided in a pre-formatted external file that is aliased in the default active.tags file. To select this file, click on the tag button and select the SI1INT item. Notice that the array fills automatically by reading the contents of the file aliased in the active.tags file and a lift vs. crank angle curve is now plotted on the screen. Some suppliers may provide data for the lift curve in camshaft degrees (the camshaft rotates once for every two crankshaft rotations in a 4-stroke engine) so there is a Angle Type pull-down menu to adjust the units on which the data is based. Lash, if not already incorporated into the lift array data, should be entered as hot lash. The lash in the system tends to change when the engine is running hot and is reduced from the cold lash. Rocker Ratio (if necessary) may be entered as well. Table 1: Intake Valve Data The fields of primary importance are the Anchors and the Multipliers, located at the bottom of the Valve Lift Profile Editor window. The Anchors allow arbitrary alignment of the valve profile within the engine cycle. The Profile Anchor denotes a point specified in the array of angle data. The Cycle Anchor denotes another point in the engine cycle in crank angle degrees. These two points align to locate the valve lift array within the engine cycle. These anchors can be parameterized (set as constants) to allow variable valve events between cases (cam phasing). The Multipliers are used to multiply every point in the valve array in either lift magnitude or angle duration. These can be parameterized (set as constants) to allow variable valve lift and duration between cases. The lift multiplier can also be conveniently used to adjust the units of the text file to the appropriate units for use in the model (multiply/divide to go from inches to mm, etc.). For this tutorial, enter the following information for valve #1, the intake valve as shown below in Table 1. This aligns the 0 degree point in the array data (in Crank Angle degrees) with the330 degree point in the engine cycle, shifting the valve event over the labeled intake stroke in the plot. It also multiplies all of the lift values by 1.414. When finished, the Valve Lift Profile Editor for valve #1 should appear as in Figure 3, below. Figure 3: Valve Profile for the Intake Valve Click the OK button to save these setting and close the Valve Lift Profile Editor. 5.2 Defining Coefficients (Flow vs. Discharge) The last piece of information required to define a valve is the coefficients. Port coefficients help describe how restricted the flow through the valve is at different lift positions. This data is usually obtained through a process of port-flow testing using a steady-state airflow rig. Click on the Edit Flow Coefficient Profiles button to open the Flow Coefficient Profiles Editor. Similar to the Valve Lift Profile Editor, data must be entered for the coefficients. This behavior is described as values for both the forward and reverse flowing direction (forward implies into the cylinder, reverse implies out of the cylinder) vs. the lift of the valve (non-dimensionalized by dividing the lift by the reference diameter). Again, there are numerous options for entering this data including:  Manually entering data into the array  Copying and Pasting an array from MS Excel (on PC platform)  Reading in a pre-formatted external file  Using a tag to alias a pre-formatted external file For this tutorial the data has been provided already in a pre-formatted external file that is aliased in the default active.tags file. To select this file, click on the tag button and select the CFTYP option. Notice that the array fills automatically by reading the contents of the file aliased in the active.tags file and a coefficient profile appears in the plot on the right-hand side of the panel, see Figure 4. This file contains information for flow coefficients as we can tell by the fact that at zero lift (zero L/D value) the coefficient has a value of 0 (zero). Flow coefficients must be entered with the first row in the array being an L/D value of 0 (zero) and forward and reverse coefficient values of 0 (zero). WAVE can also accept discharge coefficients as input. Discharge coefficients are distinguishable by the fact that the coefficient value at zero lift (zero L/D value) are non-zero. If the first row of the array is an L/D value of zero and the forward and reverse coefficients are non-zero, then WAVE assumes that the array is entered as discharge coefficients. Click on the tag button and select CDTYP to display a typical discharge coefficient profile, seeFigure 5. These two profiles are derived from the same data so either will work and is appropriate for this tutorial. Click the OK button to save these setting and close the Profile Editor. Click the OK button on the Lift-Valve Editor panel to save the settings for valve #1 and return to the Valve List panel. Figure 4: Typical Flow Coefficient Profile Figure 5: Typical Discharge Coefficient Profile the engine cylinder junction has picked the intake valve connection to use Valve #1 and the exhaust valve connection to use Valve #2. the Valve Lift Profile Editor for valve #2 (the exhaust valve) should appear as in Figure 7.0 Lift Multiplier 1. With both the intake valve (valve #1) and exhaust valve (valve #2) defined. Rocker Ratio Angle Type Coefficient Profile 0 1.0 Crank CFTYP tag Table 2: Exhaust Values .3 Defining the Exhaust Valve Click the Add button again to create a second valve that will be used to model the exhaust valve. the Valves List should appear as in Figure 6. On a multi-valve engine it may be necessary to edit the engine cylinder junction and correctly specify the valve number to use for each connection. coincidental. By default. below. This is. EXHAUST VALVE Diameter Lift Profile Cycle Anchor Profile Anchor Duration Multiplier 28 [mm] SI1EXH tag 105 [deg] 0 [deg] 1. Click the OK button to save these setting and close the Valves List panel.5. When finished. again.0 Lash Figure 6: The Valves List Follow the same steps as above but use the following information for the lift profile (the coefficients can be the same as the Intake Valve). Building a Single Cylinder Model Step 6 .2 Defining the Injector Example Input File: . Proceed to Step 6 . Chapter sections 6. Phase 1 .Figure 7: Profile Editor for Valve #2 (the exhaust valve) Save your model Click on the Save button in the toolbar to save the file.\examples\engine\TUT_si\tut_si1.wvm Example Output File: .\examples\engine\TUT_si\tut_si1.Adding the Fuel Injector SI Tutorial.Adding the Fuel Injector In this step we will add a fuel injector.1 Adding the Injector Element 6. and define the required input parameters.wps . connect it to the intake port. the injector injects fuel into the flow system (if the injector were connected to a y-junction element.2 to 0. Figure 1: Adding an Injector 6. y-junction. This will create a connection line between the two elements (the connection line must start at the injector element and be dropped onto the duct element. WAVE handles fuel injection in one of two primary ways – targeting an air-fuel ratio or injecting a specific mass of fuel. drag and drop a Proportional fuel injector above duct 2. On the Operating Point tab. click and drag the injector with the middle mouse button).2 Defining the Injector Now that the injector has been added. WAVE requires a fuel-air ratio but most frequently air-fuel ratio information is provided. Type 330 [K] into the Mixture Temperature text field. Type 0. . The heat required to vaporize this portion of the liquid fuel is pulled directly from the intake charge. or cylinder elements. This is easily overcome by using WAVE's capability to perform simple mathematical operations on constants. The easier of the two methods is to target an air-fuel ratio and let WAVE inject the appropriate amount of fuel based on the airflow. along the length of the duct element.6. all that is needed is a temperature for the injected fuel and an amount that will vaporize upon injection into the fluid stream. you cannot create a connection between the two by starting at the duct element). The proportional type injector can connect to a duct or y-junction flow element. but specific injectors can only attach to specific types of flow elements.3 into the Liquid Fraction Evaporated After Injection text field. We will define a constant named A_F and enter air-fuel ratio data in the Constants Panel. On the Position tab. this tab would be irrelevant as there is only one fluid cell in a y-junction). but in the text field for Fuel/Air Ratio. click on the injector and drag and drop a connection onto the duct2 element. Type 25 [mm] into the Distance from Left End text field to move the injector to the middle of the duct (alternatively. Double click on the injector element to open the Proportional Injector Panel. Injectors can be added to duct. On the Properties tab. Typical values are 0. A Proportional injector will always inject enough fuel to the fluid stream to match a targeted air-fuel ratio.3 for a gasoline engine. This field denotes what fraction of the liquid fuel will immediately vaporize in the fluid stream. but not cylinder elements. we can edit the properties of the injector element. This will automatically convert the air-fuel ratio to a fuel-air ratio as required. thus cooling it and increasing the density (this usually leads to a slight increase in volumetric efficiency). the model should appear as in Figure 1. type {1/A_F}. From the elements tab. To connect the injector to the flow element. we must define where. This is the simplest type of injector and is very commonly used.1 Adding the Injector Element The single-cylinder model is almost complete – all that remains is to add a fuel injector. This is the approach used in this tutorial and in a vast majority of simulations. When connected. all that needs to be defined is the targeted air-fuel ratio of the injector within the duct. below. the Proportional Injector Panel should appear as in Figures 2-5. Click the OK button to close the Proportional Injector Panel and save the data (when prompted to add the A_F constant to the Constants Panel. Figure 2: Completed Injector Editor . the default of 1.Click on the Composition tab. where the total composition of the fuel before injection can be specified. When completed. select No).0 for Liquid Fuel is suitable and can be left as is (100% of the injected fuel is in liquid state. then the vapor portion can be specified here. For this tutorial. If the aforementioned charge cooling effect is undesirable. 20% of that vaporized when injected). Figure 3: Completed Position Tab Figure 4: Completed Properties Tab Figure 5: Completed Composition Tab All that remains is to add the A_F constant to the Constants Panel. Open the Constants Panel and type the constant name, A_F, in the Name column, + row. This will automatically add a new row to the constant panel. There are no units required and the value of the constant in case 1 should be entered as 14.7 (approximately stoichiometric for the INDOLENE fuel that this simulation is using). When finished, the Constant Panel should appear as inFigure 6, below. Figure 6: Adding the A_F Constant Click the OK button to close the Constants Panel. The single-cylinder model is complete! Save your model Click on the Save button in the toolbar to save the file. Proceed to Phase 2 - Running WAVE and Creating Time Plots in WavePost SI Tutorial, Phase 2 - Running WAVE and Creating Time Plots in WavePost Running the WAVE solver will process all of the information that has been entered into the model and produce numeric results. These results can be post-processed in WavePost to produce plots and graphics for reports and presentations. Phase 2 Steps Example Input File: 1 Running a WAVE Input Check 2 Requesting Time Plots .\Ricardo\WAVE\8.0\examples\engine\TUT_si\tut_si1.wvm Example Output File: 3 Requesting Post.\Ricardo\WAVE\8.0\examples\engine\TUT_si\tut_si1.wps Processing Datasets 4 Running WAVE and Understanding the .out File 5 Introduction to Post Processing and WavePost With these five steps, we will run the WAVE solver and create some output data for postprocessing. WavePost will be used to view plots and cycle-averaged results for the model. Requesting Time Plots In this step we will add requests for plots of specific data to our existing model.1 Duct Time Plots Example Input File: . Time Plots should be requested whenever the user is aware of specific data they are interested in analyzing.\Ricardo\WAVE\8. Time Plots are plots of results over the course of a single engine cycle (the last engine cycle in multi-cycle simulations).wvm Example Output File: .Running WAVE and Creating Time Plots in WavePost Step 2 .wps .0\examples\engine\TUT_si\tut_si1. Phase 2 .4 Multiple Plots Overlaid 2. Chapter sections 2.0\examples\engine\TUT_si\tut_si1.1 Duct Time Plots 2.Show SI Tutorial.\Ricardo\WAVE\8.3 System Time Plots 2.2 Junction Time Plots 2. As there is only one cell in duct2. middle of duct is 0. Click on the OK button to close the Duct Plot List and add these plots to the Existing Plots list in the Duct Plot Panel.Suppose we are interested in observing the pressure and temperature at the mid-point of the intake port during the engine cycle. Locations are defined by a normalized value from zero to one (left end of duct is 0. such as velocity.5 location (halfway along the duct). Default Locations can be defined for commonly-used locations to be specified in multiple plots (Default Locations will appear identically for all ducts when the Duct Plot Panel is opened). right end of duct is 1). The Duct Plot Panel will open with no plots yet defined at this location. Pressure and Temperature are scalar values and. We can request Time Plots at the intake port (duct2) and WAVE will automatically create these plots at the end of the simulation. . click on the202 Temperature plot (most valid duct plots are in the 2xx range). holding the Shift button to multiple-select. from the context-menu. The location along the length of the duct from where plots should take their data is specified under the Duct Locations region of the panel. Specifying any other location along the length of the duct will create identical plots. option from the pop-up menu (see Figure 1). are stored at the center of a given cell (vector values. When complete. Clicking on the Use All Locations button will automatically create Custom Locations for every cell in a duct.5. Click on the Create Plot button to open the Duct Plot List. Figure 1: Adding Plot to duct2 The list of plots available at this location is displayed (this list is context-sensitive and generated based on the canvas item selected).. The time plots will automatically be created at the 0. Custom Locations are specific locations in the selected duct where plots should take their data. Right-click on duct2 and select the Edit Plots. as appropriate. are stored at cell boundaries).. Click on the 201 Pressure plot and then. the Duct Plot Panel should appear as in Figure 2. no location needs to be specified. right-click on the column header and select Insert Column Before or Insert Column After. in WAVE. To add locations (either Default or Custom). Click on the Create Plot button to open the Junction Plot List. We may want to create a P-V (Pressure vs.. 2. Volume) plot. Right-click on the cyl1 junction and select the Edit Plots. Click on the 111 Linear P-V Diagram and click the OK button to close the . The duct plots created above will be listed in the Existing Plots list.option to open the Junction Plot Panel..Figure 2: Duct Plot Panel with plots at duct2 Click on the OK button to close the Duct Plot Panel. simply double-click on this icon and the Duct Plot Panel will open. To edit plots at this location again.2 Junction Time Plots Suppose we desired to examine the combustion performance in the power cylinder during the engine cycle. Note the plot icon now hanging off of duct2. Note that there are many more plots in the list than in the Duct Plot List (engine cylinder plots are typically in the 1xx range). When completed. the Time Plot Panel should appear as in Figure 4. The System Location Type should be active by default when the panel opens. Note. Click on the 701 Engine Torque plot and click the OK button to close the list. the Junction Plot Panel should appear as in Figure 3. as well as sensors. Figure 3: Junction Plot Panel with plot at cyl1 2. Click the OK button to close the Time Plot Panel.. actuators. This will open the Time Plot Panel where plots can be created for the engine system.list and add the plot to the Existing Plots list. we will eventually be creating a 4-cylinder engine. Again. there is no display of the system plot on the canvas as there is not yet a canvas entity to which it can be attached. Click on the Create Plot button to open the Time Plot List for the engine system. When completed. Also note that an asterisk appears to the right of the plot type for any plot with the currently selected canvas item as a location. click on the Simulation pull-down menu and select the Time Plot. Click the OK button to close the Junction Plot Panel. below.. menu item.3 System Time Plots Although there is only one cylinder in our engine. . no location needs to be defined for system plots. To observe the behavior of the engine itself (system of cylinders grouped together). and pins (to be discussed in more advanced tutorials). No location within the junction needs to be specified for the plot as there is only one calculation point in a junction. A few engine system specific plots are available and even fewer are applicable to our system as modeled (system plots are typically in the 7xx range). . This is because these plots are allowed at duct3 as well (a P-V plot is not sensible in a duct. We could create separate plots for the duct representing the exhaust port (duct3)..4 Multiple Plots Overlaid Perhaps we wish to examine the pressure and temperature in the exhaust port and compare it to the conditions in the intake port.Figure 4: Time Plot Panel with system plot of Engine Torque 2. Right-click on duct3 and select the Edit Plots. Click on the Use All Locations button to request the plots at the center of both cells in duct3 (locations of 0. When completed. Do the same for plot 202 to add duct3 to the plot of temperature in duct2. Note that the only plots in the Existing Plots list are the pressure and temperature plots from duct2. nor is engine torque). option from the pop-up menu. click on the Add Location button to plot the pressure at duct3 on the same plot as duct2.75).25 and 0.. the Duct Plot Panel should appear as in Figure 5. With plot 201 highlighted. but it would be more useful if the data for both ports were on the same plot. The model should appear as in Figure 6 with all time plots added.Figure 5: Duct plot panel with duct2 and duct3 plots overlaid Click the OK button to close the Duct Plot Panel. Figure 6: Model with Time Plots Added Save your model . \Ricardo\WAVE\8. beyond the behavior in the intake and exhaust ports. etc. Clicking on the double-arrow button will move all datasets form a Model grouping in the the Requested Datasets list. menu item from the Simulation pull-down menu. It also allows the user to do more advanced post-processing to be discussed later in this tutorial.) at numerous points throughout the network or is unsure. By default. which are datasets grouped together that are always available.g. This is more convenient if the user wishes to have the data (e. Temperature. To request a specific dataset that we would like written to the simulation output file. ahead of time.wps 3. We have yet to request any data to be output after the simulation is run through the WAVE solver.\Ricardo\WAVE\8. which behaviors we will be interested in viewing results for at the end of the simulation. Pressure. as opposed to certain locations as in the case of Time Plots. no matter which junctions or physical models exist in the simulation.. highlight one by clicking on it and then click on the single arrow button pointing to the right to add it to the list of Requested Datasets (datasets can be multipleselected by holding down the Shift key to highlight a span of datasets or the Ctrl key to highlight multiple. Phase 2 .. Proceed to Step 3 .1 Basic Datasets Chapter sections Example Input File: .1 Basic Datasets Suppose we are not sure.wvm 3. individual datasets).0\examples\engine\TUT_si\tut_si1. . Later analysis might require extensive amounts of data that we didn't request plots for ahead of time! It may also be inconvenient to return to WaveBuild and request more plots and rerun the model.Requesting Post-Processing Datasets Show SI Tutorial.Click on the Save button in the toolbar to save the file. the Basic models are listed.0\examples\engine\TUT_si\tut_si1. so the Requested Datasets list should be blank. especially if the model takes a very long time to run! We can avoid some of this by requesting Post-Processing Datasets in advance. Open the Postprocessing Output Panel by selecting the Postprocessing Output.2 Valve Datasets Example Output File: .Running WAVE and Creating Time Plots in WavePost Step 3 . 3. at which locations this data will be required for post-processing.Requesting Post-Processing Datasets In this step we will request that particular data that we may be interested in later be output for the entire network. change the Models option menu to Valve.For this simulation. When completed. This will make the Available Datasets list change to those contained in the Valve subset. All subsets besides the Basic subset are available depending upon the junctions or physical sub-models included in the analysis. .2 Valve Datasets At the top of the Postprocessing Output Panel. FLOW_COEFFICIENT. Figure 1: Requesting Basic Datasets 3. CF). When completed. and LIFT_OVER_DIAMETER to the Requested Datasets list. This will allow us to observe the difference between the coefficient used and the one not-selected (CD vs. the Postprocessing Output Panel should appear as in Figure 2. the Postprocessing Output Panel should appear as in Figure 1. select the VELOCITY and VOLUMETRIC_FLOW datasets. Highlight and add DISCHARGE_COEFFICENT. \Ricardo\WAVE\8.out File 4. Proceed to Step 4 .0\examples\engine\TUT_si\tut_si1. Chapter sections 4. Phase 2 .2 The .wps .Figure 2: Requesting Valve Datasets Click on the OK button to save the changes and close the panel.out file Show SI Tutorial.\Ricardo\WAVE\8. Save your model Click on the Save button in the toolbar to save the file.Running WAVE and Creating Time Plots in WavePost Step 4 .0\examples\engine\TUT_si\tut_si1.out File In this step we will run the model file through the WAVE solver and learn to parse the output file. In this and the following step. all output files created during the simulation will be examined and defined as to their purpose and use.1 Running the Solver 4.Running WAVE and Understanding the .1 Running the Solver Example Input File: .Running WAVE and understanding the .wvm Example Output File: . xml.wvm extension. This information may be useful for debugging purposes in simulations that fail during run-time. discussed and analyzed earlier after the input check. To run the model through the actual WAVE solver there are two options:  Run the model in screen mode by clicking on the Run Screen Mode button in the toolbar  Run the model in batch mode by clicking on the Run Batch Mode button in the toolbar Screen mode runs the model at high priority while sending standard output to the screen. There should now also exist . a shell will open. printing output in real-time for the user to examine (output is also printed to the .wps file). No indication of the process is given.out.out file. the window will minimize. To this point. . and . Run the solver using either method and close the shell (if necessary) when the simulation is complete. Open the . noting the version of the solver being used. Row (1) gives an abbreviation for what each column of data is displaying.out file. . When the simulation is finished.hlt extension.hlt file will not be discussed here but this file will be automatically deleted upon successful completion of the simulation. note the output from the simulation during run-time.out file).wps files as well (a . On PC. It is a simple XML format file that can be observed in any web browser by changing the filename extension to . The . .sum. BAS:TIME I*** REQUESTED PLOT ID`S AND TITLES: PLOT # 1 201 Pressure LOCATIONS: DUCT: duct2 PLOT # 2 202 Temperature LOCATIONS: DUCT: duct2 PLOT # 3 111 Linear P-V Diagram LOCATIONS: JUNC: cyl1 PLOT # 4 701 Engine Torque BAS:DATASETS DUCT: duct3 DUCT: duct3 Next.2 The . we have been building the model and saving it along the way into a file with a .rp file will have also been created for reverse compatibility with an older post-processor and will not be discussed – it is obsoleted by the .out File While the simulation is running. 4.out file using any common text-editor and examine. If this file exists when the simulation completes. now contains additional data about the simulation. the process is detached from the current shell (similar to executing at the shell prompt with the "&") and run in the background. WaveBuild will prompt you to first save the file before running.The model has been run through an input check and is all set to create the requested data for postprocessing. and the simulation will run "quietly" with no output to the screen.wvd. it usually indicates that the simulation failed while running in WAVE. the prompt will return in the opened shell. First note the added requests for plots and datasets called out when the input file is parsed. On UNIX. If the model has been altered in any way and not yet saved (noted by the asterisk next to the filename in the title bar). Batch mode runs the model at reduced priority while sending standard output to the . The . Status of the simulation can be determined using the "ps -ef" command. WAVE will create a temporary file with the . A shell will open and the simulation will pass by. 68 0. 2.1447E-02 PCYL 1. They are.680E 1. .990 11.680E 1.8585 PHI(1) = 0. When auto-convergence conditions are satisfied (14).967 1353. Rows (4+) will be a summary of every individual cylinder in the system for each engine cycle followed by a engine system summary for each cycle.9666 PHI(1) = 0.379 -1.1073 VOLEF(TOT) = 0.373 -1.58 0.3 0.00 0. Mass Airflow (kg/hr). Equivalence Ratio.959 -1. begin at IVC for cylinder #1 unless otherwise specified in the General Parameters panel).8 0. ENG: ENG ENG: ENG ENG: ENG I*** ENG: ENG I*** ENG: ENG I*** ENG: ENG I*** NC ICYC ISTEP AIR-KG/HR VOLEF TEXH PHI IMEP PMEP IHP ISFC 1 0 1 0.000 0. Indicated Specific Fuel Consumption [g/kW*hr].1346E-01 Pvariance = 0. Cylinder Temperature at IVC [K].569 385.966 1356. Exhaust Port Temperature [K].1391 1 3 2265 79.680E 1.210 32.61 0.235 -1.990 12.575 381. and limiting elements in the system. The column titles as labeled in row (1) relate to the lines summarizing individual cylinder performance.00 0.569 385. Our engine is a 4-stroke engine so there are 720° in a single engine cycle with 776 timesteps in the last engine cycle.568 385.990 AUTO-CONVERGENCE CONDITIONS MET: Uvariance = 0.883 1 2 1489 79.00 1.25 -2.202 31.000 0. Cylinder Pressure at IVC [bar].680E Next. IMEP [bar]. well-built WAVE models won't have a timestep below 0. Although there is no hard and fast rule.2228 VOLEF(TOT) = 0. number of timesteps.0000 PHI(1) = 0.0000 VOLEF(TOT) = 0.Row (2) is a summary for Cylinder #1 during engine cycle 0.1375E-03 Pvariance = 0.966 1356.9 0.2227 VOLEF(TOT) = 0. it is usually due to poor modeling practice (extremely small element size within the model). WAVE will run one more engine cycle and then finish the case.990 AUTO-CONVERGENCE: Uvariance = 0. PMEP [bar]. If the timestep is smaller than this.8932E-04 Pvariance = 0.966 1278.9663 PHI(1) = 0. Engine Cycle (cumulative from start of case).000 1 1 723 70.990 AUTO-CONVERGENCE: Uvariance = 0. This happens regardless of whether or not convergence conditions are satisfied in the following engine cycle. by default. typical. Row (3) is a summary of engine system performance for engine cycle 0.000 0.9 0.211 32.2227 VOLEF(TOT) = 0.858 413.59 0.990 AUTO-CONVERGENCE CONDITIONS MET: Uvariance = 0.50 0.100 -3.1°. the start-up cycle (WAVE simulations.5 0. and Trapped Fuel/Air Ratio at IVC. note the information on elapsed time. in order – Cylinder Number.28 sec.013 TCYL 301. The number of timesteps can be used to calculate the average timestep size in CA° over the last cycle (CA° per cycle / #timesteps).990 12. Note in this simulation that duct4 is the limiting element. Starting at engine cycle 3. 0 sec.1 FTR 0.0 0.56 0.9662 PHI(1) = 0. Only Cylinder #1 will have results for engine cycle 0.883 -1. This yields an average timestep size of approximately 0.569 385. if the convergence detection was activated in the General Parameters panel.606E 1.5334E-03 Pvariance = 0.2 0.3915E-01 1 4 3041 79.0 0. Timestep number (cumulative from start of case).57 0.93° – close to the default maximum timestep size of 1° set in the General Parameters panel.58 0. Indicated Horsepower [hp]. with sub-volumes 1.370 -1. The limiting element information can be useful in finding an unreasonably small Discretization Length or Overall Length (for a duct) or Volume (for a y-junction) that may be slowing the simulation down dramatically.990 12.4454E-02 1 5 3817 79.8 0. Volumetric Efficiency.2 0.55 0. and 4 showing up in the list ELAPSED TIME OUTPUT: TIME STEP OUTPUT: CPU TIME (IN THIS CASE) = WALL CLOCK TIME = TOTAL STEPS IN LAST CYCLE = 776 0.9664 PHI(1) = 0.213 32.000 900. a line (8) denoting auto-convergence conditions is printed to the output.1 0.2304 VOLEF(TOT) = 0. 5 1.5595 0.084 0.RAT. Operating Conditions.02361 0./ PLEN. general result information is printed in tabular format. (GAS IN / GAS TR.FR.706 0.RAT.035 EGR FR.1 0.1 -23.821 114.248 1.EFF.0 610.3 DUCT/VOL: duct4/4 18.) = 1. (FRESH TR.1 DUCT/VOL: duct4/2 11. COMBSTART IGNDEL bar/deg deg kW deg deg deg deg (PLENUM) deg deg -----------------------------------------------------------------------------------------------------------1 2. Breathing Quantities. The output contained from this point forward varies for what is included in the model (turbine/compressor.RATIO IMEP PMEP IHP TEXH RES(%) EGR(%) PHI kg/hr bar bar K -----------------------------------------------------------------------------------------------------------1 79.5 ------------------------------------------------------------------------------------------------------------TITLE: SI Tutorial. REF.3195 0. and Engine Out Emissions. printable for records or reports. TRAP.).4 400.3088 0.988 0.020 SCAV./ FRESH IN ) = 1.927 859.5 -23.9 1.) = 1.02209 0.56 0.9747 -24.1 12.0 1243.0000 0. Results included are Final Output of all elements in the system (ducts and junctions).02360 9.8 -23. (FRESH TR.1 duct4 orif2 Exhaust 400. ) = 0.935 1.0 330.02209 12.965 TOT.020 SCAV.DEL. 4-Cylinder Gasoline Engine at 6000 rpm ------------------------------------------------------------------------------------------------------------ E N G I N E S U M M A R Y -----------------------------------------------------------------------------------------------------------NC MASS IN VOL. Engine Geometry.000 12.121 0. (FRESH IN / PLEN. Examine this portion regularly to grow more familiar with WAVE output for different models! -----------------------------------------------------------------------------------------------------------TITLE: SI Tutorial.000 DEL. REF.105 0.0 duct3 cyl1 orif2 400.0 0. 4-Cylinder Gasoline Engine at 6000 rpm ------------------------------------------------------------------------------------------------------------ -----------------------------------------------------------------------------------------------------------F I N A L O U T P U T O F D U C T S -----------------------------------------------------------------------------------------------------------Duct Junction TWALL TAV PAV PMAX PMIN UMAX UMIN MACH FLOW A [K] [K] [bar] [bar] [bar] [m/s] [m/s] NUMBER [kg/s] [cm^ duct1 Intake 300.988 1.LIMITING ELEMENT % STEPS (DOES NOT HAVE TO ADD TO 100) ------------------------------------------------------------DUCT/VOL: duct4/1 69.02362 6.EFF. REF.6 0.EFF (GAS IN / PLEN.02361 0. and Valve and Emissions specific output.460 0.8 0.865 114. Fuel Burn Progress Summary.000 -----------------------------------------------------------------------------------------------------------F U E L B U R N P R O G R E S S S U M M A R Y ------------------------------------------------------------------------------------------------------------ .0 -31.821 0.4 389.0 0.EFF. ) = 0.402 1. Engine Summary.0 1160.5 orif1 300./ GAS TR.995 1.9 859. (RESID IN / GAS IN ) = 0./ GAS TR. etc.049 0.978 0.6 0.EFF (AIR IN / AMB. emissions modeling.989 1.0000 1.4 -437. 3.0 1107.58 1356.0 1143.EFF.3423 0.210 32.9766E-03 10.37 -1. (FRESH TR.5 -17.3 0.0 0.966 TRAP.0 297.121 1.337 0.4 Finally.044 0.9663 1.5 220.507 0. ) = 0.35 0.596 808.) = 1.02361 0.987 1.020 RESID.8 -23. REF.924 0.0 405. (RESID TR.0 -634. Predicted Performance.EFF.4 0.4 400.9903 -----------------------------------------------------------------------------------------------------------NC DPMAX TH_DPMAX HTR EVO EVC IVO IVC VOL.0 6.3423 1.0 294.0 310.0 299.000 0.02209 9.965 CHARG.000 -----------------------------------------------------------------------------------------------------------B R E A T H I N G Q U A N T I T I E S -----------------------------------------------------------------------------------------------------------AMB.6 0.34 105.6 duct2 orif1 cyl1 310.) = 0.3088 0.VOL.4 294.929 110. EFF.9663 I #1 MAX DP/DTH [bar/deg I H.000 I PISTON VEL.TIMING [deg I AMB.PORT PR[bar] = 0.00 16.40 I (MULTI) [lbm/hr I FUEL LHV [MJ/kg] = 43.EFFICIENCY [%] = 37.3662 I [lbm/hp/hr] = 0.18 I [ft/min] = 3228.15 I FRICT. [%] = 3.00 I EXH.000 I (BRAKE SPC.PORT TEMP[K] = 291.ENTH.4 I [psi] = 153.9524 I I [in] = 3.97 I COMPRESSION RATIO = 10.3928 I NUMBER OF CYLINDERS = 1.45 I PUMP.93 I #1 VOL. LIFT [mm] = 12.90 I I FUEL RATE [kg/hr I O = 0.7 I I ---------------------------------------------------------------------------------------------------------P R E D I C T E D P E R F O R M A N C E (I D E A L G A S E S) ---------------------------------------------------------------------------------------------------------I INDIC.2228 I BSFC [kg/kW/hr] = 0.83 I FRIC.37 I BMEP [bar] = 10.[m^3] = 0.)[g/kW/hr --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------TITLE: SI Tutorial.000 I I [in^3] = 23.00 I WRIST PIN OFFSET[mm] = 0./CYL.49 -----------------------------------------------------------------------------------------------------------TITLE: SI Tutorial.300 I [inHg] = 28. POWER [hp] = 32. ENERGY BALANCE:(MULTI) I FRESH AIR IN[kg/hr] = 79.ENTH.GAS T[K I PUMPING WORK [%] = -3. WEIGHT = 101.(DELIVERED) = 0.09 -0. I I I H.000 I I [in] = 3. I #1 INT.000 I [g/hr] = 2. TEMP.000 I [degF I IND.10 I BORE/STROKE = 0.41 23.56 I I 1% FUEL PWR/CYL [W I FUEL MOLEC. TRAN.93 I PMEP [bar I IND.[mm] = 28. INTAKE VALVES = 1.9780 I [psi I FUEL TYPE (C:H:O) C = 7. TORQUE [N*m I ISAC [kg/kW/hr] = 3.4365E-04 I ENGINE TYPE ---------------------------------------------------------------------------------------------------------I INT.460 I [degF I I BRAKE POWER [kW] = 20.00 I EFFECTIVE CR (VC-TDC I BORE [mm] = 78.1259 I (BRAKE SPC.42 -10.61 I #1 INT.)[g/kW/hr] = 0.43 I (WET) [lbm/hr] = 175. [m/s] = 16.96 I INJ.CRANK ANGLES [deg ATDC] VS.[mm] = 35.228 I CLEARANCE VOL. [%] = 9999. I VOL.22 8. 4-Cylinder Gasoline Engine at 6000 rpm ------------------------------------------------------------------------------------------------------------ .52 I [ft*lbf] = 24.EXH.0 I I STROKE [mm] = 82.[bar I [degF] = 76.383 I [kW] = 0.36 36. I #1 FUEL / SHOT [kg I [btu/lbm] = 0. ROD LENGTH[mm] = 150.000 I NO. VALVE DIA.DURATION [deg I H = 13. FUEL MASS BURNT: NC %BURNT: 0% 1% 2% 5% 10% 25% 50% 75% 90% 95% 99% 1 -24.1856E+05 I I I (A/F) STOICH = 14.000 I #1 CA AT PMAX [deg I DEBIT INTK.2598 I IMEP(GROSS) [bar I [lbm/hp/hr] = 0.000 I #1 IVC [deg] ---------------------------------------------------------------------------------------------------------O P E R A T I N G C O N D I T I O N S ---------------------------------------------------------------------------------------------------------I RPM = 6000.)[g/kW/hr] = 0. START[deg I [inHg] = 29.(PLENUM) = 0.35 -16.70 I #1 CA AT MAX DP/DTH[de I IMBALANCE [%] = 9999.1 I INJ.662 I RESIDUAL FRAC. VALVE DIA.92 28.73 I #1 EXH.4272 I [psi I IND. [K] = 298.43 I BRAKE EFFICIENCY[%] = 32.000 I HC EMISSIONS(C1) [ppm] = 63. TORQUE [N*m] = 38.9747 I [psi/deg I BLOWBY AT RING1 [%] = 9999.000 I [inHg] = 29.9903 I #1 MAX AVG.09 I [psi I IMEP(NET) [bar] = 12.000 I #1 EXHAUST TEMP [K I [lbm/hp/hr] = 5. (%FUEL ENER.(IN-CYL)[%] = 15.(IN-CYL)[kW ---------------------------------------------------------------------------------------------------------E N G I N E O U T E M I S S I O N S ---------------------------------------------------------------------------------------------------------I NOx [ppm] = 0.[%] = 9999.00 I #1 EVO [deg] I MAX. PRESSURE [bar] = 1. I TRAPPING RATIO = 1.56 I #1 PMAX [bar I NET PISTON WORK [%] = 37.67 I BRAKE TORQUE [N*m] = 33.INJ.TRAN.9883 I #1 IGN DELAY [deg I AMB.96 I CO EMISSIONS [ppm I NOx AS NO2 [g/hr] = 0. EXHAUST VALVES = 1.275 I AUXILIARY POWER [hp] = 0.61 I FMEP [bar I [psi] = 179. TORQUE [N*m I [ft*lbf] = 28.4 I [psi I AVAIL. I PHI TRAPPED = 0.EFF.38 I MID.075 I CON.57 I MAX. [l] = 0.58 I BRAKE POWER [hp] = 27.640 I #1 EVC [deg] I I I #1 IVO [deg] I NO.78 -7.622 I [g/hr I (BRAKE SPC.PRESS.PORT PR[bar] = 0.49 -14.8 I [psi I ISFC [kg/kW/hr] = 0. I A/F TRAPPED = 14.0 I [degF] = 64. LIFT [mm] = 8.27 I #1 COMB. 4-Cylinder Gasoline Engine at 6000 rpm ------------------------------------------------------------------------------------------------------------ E N G I N E G E O M E T R Y ---------------------------------------------------------------------------------------------------------I DISPL. 107 ---------------------------------------------------------------------------------------------------------- CYCLE AVERAGED AMBIENT EMISSIONS ---------------------------------------------------------------------------------------------------------I I NO I NO2 I CO I HC I I AMBIENT I [g/hr] I [g/hr] I [g/hr] I [g/hr] I ------------------------------------------------------------------------------I Exhaust I 0.5540E-05 I 1.000 I 0. We will also observe how WavePost displays Cycle Average quantities using datasets requested in WaveBuild.ENGINE CYLINDER BACKFLOW ---------------------------------------------------------------------------------------------------------I I BEFORE EVC I AFTER EVC I I CYL I AMOUNT[kg] I % OF TOTAL I AMOUNT[kg] I % OF TOTAL I -------------------------------------------------------------------------I 1 I 0.5540E-05 I 1.000 I 0.4 Time Plots in WavePost 5.Introduction to Post-Processing and WavePost Show SI Tutorial.wps File 5.1751 I 0.0\examples\engine\TUT_si\tut_si1.2 I ---------------------------------------------------------------------------------------------------------CYCLE AVERAGED ENGINE CYLINDER EXHAUST INDICATED SPECIFIC EMISSIONS ---------------------------------------------------------------------------------------------------------I I NO I NO2 I CO I I CYL I [g/kW/hr] I [g/hp/hr] I [g/kW/hr] I [g/hp/hr] I [g/kW/hr] I [g/hp/hr] I [g/k ---------------------------------------------------------------------------------------------------------I 1 I 0. Phase 2 .621 I I Intake I 0.8268E-06 I 0.000 I 0.sum File 5.2 The . Chapter sections 5.1751 I 0.5 Cycle Average Results Example Input File: .0\examples\engine\TUT_si\tut_si1.174 I ---------------------------------------------------------------------------------------------------------ENGINE INTAKE VALVE BACKFLOW ---------------------------------------------------------------------------------------------------------I I BEFORE EVC I AFTER EVC I I I CYL VAL I AMOUNT[kg] I % OF TOTAL I AMOUNT[kg] I % OF TOTAL I REVERSE ANGLE I -------------------------------------------------------------------------------------------I 1 1 I 0.8268E-06 I 0.174 I 572.000 I 0.\Ricardo\WAVE\8.000 I 34.000 I 2.\Ricardo\WAVE\8.wvd File 5.Introduction to Post-Processing and WavePost In this step we will examine the files created by WAVE for post-processing and use WavePost to examine and create Time Plots from the simulation.wvm Example Output File: .wps .000 I 0.1 The .000 I 0.000 I 0.02 I ---------------------------------------------------------------------------------------------------------- Proceed to Step 5 .000 I 0.000 I 0.Running WAVE and Creating Time Plots in WavePost Step 5 .3 The .000 I 0. 193 DELEFF= 1.931245 TH0%_5%B1= 13.2360524E-01 DMLduct3= 1.2362354E-01 DMLduct4= 1.412287 BSFCSI= 0.sum file and examine: SUM: CASE: 1 -----------------------------------------------------------------------------------------------------------TITLE= SI Tutorial.in WavePost 5.2598259 BSFCBR= 0. 4-Cylinder Gasoline Engine at 6000 rpm TIME= 0.2360319E-01 DMLduct2= 0.sum File At the end of the simulation.0000 THEVC1= 405.2220210 TH50%B1= 8.000016 PVOLEF1= 0.55498 FMEPBR= 25.4380000 ELAPSED_TIME= 0.459644 VOLEFD= 0.wvd File WAVE also will create a .wvd file.9653720 DELEFT= 1.141593 A_F= 14.072708 DFLduct3= 0.043934 TH_DPMAX1= 0.087250 TH25%B1= -0.9902628 PPMNO= 0.308751 DMRduct4= 0.2 The .274573 ISFCBR= 0.83043 BMEPSI= 10.36994 IMEPBR= 179. Cycle-averaged results are single-number values detailing results that are calculated as an average over the entire last cycle in the simulation.000000 CYCLE= 5.728034 DPTOTLduct4= 1.857011 DPTOTLduct3= 1. etc.000000 PAMBE= 1.71 TRAPRT1= 1. The . all constants.66922 NMEPBR= 179.000 # 5.70000 PMAXSI1= 61.020265 SCAVRA= 0.30476 IMEPSI1= 12. Open the .5594955 $case= 1.9782504 DPRduct3= 0.4108 ITORQSI= 38.1000000 CPU_TIME= 0.9351169 DHduct3= 1.wvd file. but is intended for use by the WavePost postprocessor.000000 $subcase= 0.020247 EGR= -0.4271538 ISFCSI= 0. .1634780E DVLduct1= 20.58212 IMEPSI= 12. Data for requested time plots and datasets are stored in the .054536 DPTOTRduct3= 1.93407 BPOWKW= 20.1258814 PPMCO= 0.59414 FTORQ= 5.062538 DPTOTRduct4= 1.96400 GMHC= 0.2227600 ISACSI= 3.1385 TEXH= 1356.41493 TH90%B1= 23.9663104 AFTRP1= 14.5500 DPLduct1= 0. The .45019 IHP= 32.2815 DTRduct1= 297. both installed with WAVE.000000 GMCO= 0.33776 DTLduct1= 299.031677 DVLduct4= 171.9336 HTREVP1= -124.1722039E-04 BHP= 27.4108 GMEPSI= 13. At the end of the output for each case.95363 DVRduct1= 20.9657 PMEPSI= -1.sum file is a simple ASCII text file that can be viewed using any text editor.000000 TIME_RUN= 0. renaming. are also listed with the values used.3115508E-01 DPTOTLduct2= 1.34658 TH1%B1= -16. Power.92243 TH0%_2%B1= 9. and Fuel-Consumption (a list of what each name in the .000000 DMRduct3= 1. If necessary.3194962 DTRduct2= 294.3535 DPLduct2= 0.18555 DFLduct2= 0.34658 VOLEF1= 0.3423029 DMRduct2= 1.7042 DFRduct4= 0.71 THEVO1= 105.308751 DTLduct4= 1107. The .000000 $pi= 3.9891816 DPRduct1= 0.000000 TAMBE= 298.5681 TH0%B1= -24.92454 TH_PMAX1= 14.00000 COMBSTART1= -24.sum file contains a group of name=value pairs that detail the cycle-averaged results for each case in the simulation.516422 AUXPOWKW= 0.1 The .25933 TH0%_90%B1= 48.wvd file is a binary file (not legible in a text-editor) written in Ricardo SDF (Standard Data File) format and is also intended for use by the WavePost postprocessor.000000 HTR1= 10338.sum file equates to can be found in the WAVE Help).83508 HTCEVP1= 279.70000 SPEED= 6000.2360543E-01 DFRduct3= 0.000000 HTRIVP1= 18.000000 PPMHC= 63. WAVE should have created a .9873856 DHduct1= -0.36994 EGR%1= 0.9882348 DPRduct2= 0.3662175 HTR%= 15.92595 FRICT%= 5. Examples include Torque.9779931 TINT= 291. This file is vital to running the WavePost post-processor and should not be tampered with by editing.210373 PMEPBR= -17. this data can be extracted by using either the SDFBrowser or the sdftoascii command-line program.000000 DPLduct3= 0.sum file.000000 PHITRAP= 0.60529 TORQBR= 24.390 DPRduct4= 0.000735 TH75%B1= 16.7283791E-03 BSHC= 0.9765625E PEXH= 0.9663104 HTR= 10338.001466 DVRduct2= 20.56872 TH0%_10%B1= 17.97836 DFLduct1= 0.26900 TH2%_90%B1= 38.48995 TH10%B1= -7. including pre-defined constants.0000 OVERL1= 75.9747397 DPMAX1= 2. The .58031 GMEPBR= 196.9949624 DHduct4= 2.339182 RES%= 3.2208986E-01 DMLduct1= 0.2208986E-01 DFRduct2= 0.2208944E-01 DFRduct1= 0.0000 AIRKGH= 79.56063 AIRRPM= 0.1326010E-01 FUEKGH= 5.9882348 DHduct2= -0.wvd file also stores a copy of the network layout and other key information for post-processing. 5.wps file at the end of the analysis.3 The . The WavePost GUI will open and automatically load the . When WavePost is launched directly from WaveBuild.5.wps file is also an XML format file that can be observed in any web browser by changing the filename extension to. it will look in the working directory for a . WAVE will create a . It is simply a session file (template) for the WavePost postprocessor detailing what information to extract from the . The .4 Time Plots in WavePost Launch WavePost from WaveBuild by clicking on the WavePost button in the toolbar . The network should appear in the main WavePost window identical to its appearance in WaveBuild (see Figure 1).sum files from the same simulation are assumed to be the results set for analysis.wps file with the same prefix as the currently loaded .wps File When any time plots are requested in WaveBuild. If it exists.wps created by WAVE (since we requested time plots in WaveBuild). the file is opened in WavePost and the . Figure 1: WavePost GUI .wvm file in WaveBuild.wvdand .xml.wvd file for requested time plots that are created during the WAVE simulation. .. etc. Plots are categorized as Time Plots. select the Custom option and then click on the Edit. highlight the single set that is available (named filename. or SDF.. such as the data line. and Pasted between plots. The Time Plots that we requested in WaveBuild have been automatically created and are listed in the tree under the Time Plots folder. pull-down menu item. In the Independent Variable (X) section of the panel. Highlight the Junction Cyl1 Intake 1 option in the Elements option menu and select Valve Lift Over . option – a blank time plot window will open... Elements of the plot. Data on an existing plot can also be exported to an Excel file (on PC) or to an ASCII text file by selecting the File > Export. Plots can be printed directly to a printer or to an image file by clicking on the Print button toolbar... This data has been stored in the .. Notice that this plot has a data line for the single element in duct2 as well as both of the elements in duct3.. or. Copied. Figure 2: Time Plot of Pressure in duct2 and duct3 Each plot can be individually opened and edited.wvd:Case 1). or TCMAP Plots.. ASCII.. Right-click on the Time Plots folder and select the Add Time Plot. Sweep Plots. in the The plots that were pre-requested in WaveBuild are already created and listed under the Time Plots folder.. But we also requested some Basic and Valve Datasets. where we decided to "Use All Locations".... Individual data curves can be hidden through the Curve Selector Panel (Tools > Curve Selector. are all selectable and changeable. button to open the X Axis Selector Panel.. on PC. option from the Add pull-down menu to open the Time Data Panel.wvd file and we can now create our own time plots using this data. Spatial Plots. Double-click on the Pressure plot to see the result (see Figure 2).) or imported from an ASCII text file. the title. the axes.. Select the Data. non-dimensionalized valve lift (L/D).). We will create an overlay of Valve Flow Coefficient (CF) and Valve Discharge Coefficient (CD) vs.. Ricardo SDF-formatted file. In the Output Sets option menu..). from an MS-Excel file (File > Import > Excel..The Results Frame in the lower right corner of WavePost shows all results available in the current session file. Data can be added to a plot from the existing results (Add > Data. Data can also be Cut. A single plot can also be Cloned (File > Clone) to create an exact copy of a plot to use as a template for new data. in the "Plot" pull-down menu. paste a second data curve on the same plot. Finally. Figure 4: Time Data Panel Click the OK button to save the settings and close the panel. The data curve for Flow Coefficient will appear in the Time Plot and the plot title and axis labels will be automatically generated. Highlight the data curve and. under the Elements option menu. Back in the Time Data Panel. Double-click on the X-axis and edit the label to read "L/D". .Diameter in the Variables option menu. the Time Plot should appear as in Figure 5. Close the Time Plot and note that a fifth plot is in the list under the Time Plots folder named "CF and CD". the Time Data Panel should appear as in Figure 4. change the option from "Cyclic" to "XY". Figure 3: X Axis Selector Panel Click the OK button to save the selections and close the panel. highlight the Junction Cyl1 Intake 1 option and pick Valve Flow Coefficient in the Variables option menu. The X Axis Selector Panel should appear as in Figure 3. below. Change the Variable to VALVE:DISCHARGE_COEFFICIENT and click on the OK button to save the change. Double-click on the plot frame (easiest to do at the top or right-edge of the plot) and click in the Grid checkbox. Click on the Edit Databutton and then click on the Modify Data Source button. Don't forget to update the Legend in the Curve Panel to reflect the change from flow to discharge coefficient. using the Copy and Paste toolbar buttons. Double-click on the plot title and edit it to read "CF and CD". Double-click on the second data curve in the legend to open the Curve Panel. Double-click on the Y-axis and edit the label to read "Valve Coefficient" (delete the word Flow). When finished. When finished. Location 0. Right-click on duct1 to create a time plot of Velocity at location 0.0 (Figure 6) and right-click oncyl1 to create a time plot of Pressure (Figure 7).0 .Figure 5: CF and CD Plot for cyl1 Intake Valve Time plots can also be made quickly by right-clicking on an element in the flow network diagram and selecting a variable to plot. Figure 6: Velocity Time Plot at duct1. then click the OK button to close the panel. These can be controlled in the Contour Map Panel (accessible from the Average Panel. Figure 8: Cycle Average Velocity Save your file . or by double-clicking on the contour bar at the bottom of the canvas) using the slider bars or by typing numerical values in the given text fields. In the Results Frame in the lower right corner of WavePost. This will open the Average Panel and will automatically redraw the model canvas to display the flow network as a simple scaled model.Figure 7: Cylinder Pressure Time Plot at cyl1 5. This creates the Network Display in the Average folder named Case #1 Velocity.5 Cycle Average Results in WavePost Any dataset that stores data for elements (cells/junctions) which was requested in WaveBuild can be displayed as color contours on the flow network diagram. the ducts and junctions are redrawn with relative diameters displayed and color contours to represent the selected variable. right-click on the Average folder under the Network Displays folder. The scale at the bottom of the window automatically sets upper and lower bounds by using the highest and lowest calculated values from the dataset. Change the name to Case #1 Velocity and select the Velocity variable. 0\examples\engine\TUT_si\tut_si4.wps) by selecting the Save As.wvm Example Input File: .wvm Example Output File: .) since WAVE will overwrite the file every time the solver is run.\Ricardo\WAVE\8.wps file to the same directory with a new name. Proceed to Phase 3 . etc.Multi-Case. The 4-cylinder model will be analyzed over a range of operating speeds by creating a multi-case analysis..out and . It is important to save a WavePost file under a different name when it has been edited (plots created. If you would like to rerun the model file and still have access to the plots and network displays you've just created save the . 4-Cylinder Model and Creating Sweep Plots in WavePost Show SI Tutorial. option from the File pull-down menu. .Save this WavePost session file (. Phase 3 .\Ricardo\WAVE\8.sum Files 5 Creating Sweep Plots in WavePost . we will create a parameterized 4-cylinder model that runs un-throttled over a range of 1000-6000 rpm.0\examples\engine\TUT_si\tut_si1. 4-Cylinder Model and Sweep Plots in WavePost A 4-cylinder model can be built using the single-cylinder model as a template.Converting to a MultiCase..wps With these five steps. Phase 3 Steps Optional Starting Point: 1 Copying and Pasting the Single-Cylinder Model 2 Joining the Cylinders Using a Simple Y-Junction 3 Creating a Multi-Case Speed Sweep 4 Changes in the .0\examples\engine\TUT_si\tut_si4.\Ricardo\WAVE\8. We will then observe the behavior of the engine over the speed range by creating Sweep Plots in WavePost. changed. Phase 3 . including the attached ducts representing the ports.\Ricardo\WAVE\8.1 Detaching the Ambient Junctions .Converting to a MultiCase.Show SI Tutorial.\Ricardo\WAVE\8.0\examples\engine\TUT_si\tut_si4.3 Creating an Engine .wps Block Icon 1.0\examples\engine\TUT_si\tut_si4.1 Detaching the Ambient . Chapter sections Example Input File: 1.2 Copying and Pasting the Example Output File: Network 1. The engine information then needs to be updated to reflect the addition of three new cylinders.wvm Junctions 1. Copy and Paste functionality can be used to create three copies of the singlecylinder network. 4-Cylinder Model and Sweep Plots in WavePost Step 1 .Copying and Pasting the Single-Cylinder Model Time and effort can be saved when creating our 4-cylinder model by using the existing single-cylinder model as a template. This will detach the duct from the ambient. All of the selected items within the box will be highlighted in red. option from the menu to open the Canvas Properties panel. draw a box around the ducts and engine-cylinder network to select the entire system (be careful not to draw the box around the ambient junctions). the model should appear as in Figure 1. thus no plots are dangling off of any of the newly created ducts/cylinders (feel free to request new plots if desired).. . drag the Intake ambient further to the left. with the attached ducts representing the intake and exhaust ports. Repeat for the Exhaust ambient. Using the left mouse button.The single-cylinder model currently has Ambient junctions at both ends. These ambient junctions can be detached and moved aside for the time being. Repeat for the end of duct4 attached to the Exhaust ambient. Holding the middle-mouse button down. We can therefore copy and paste the existing singlecylinder network three times to create the other cylinders in our 4-cylinder engine. We don't need to include these when replicating the engine network. Click on the Copy button in the toolbar . named Intake and Exhaust. to move it out of the way. To hide the plots that currently exist on the network. Using the middle mouse button. drag the end of duct1 out onto the canvas and release the mouse button. Middle-click on the end of duct1 that is attached to the Intake ambient. moving it further to the right. right-click anywhere in the white canvas area and select the Edit Canvas Properties. Click on the canvas beneath the cyl1 junction and a duplicate network will be created. Figure 1: Ambients Detached from Ducts 1. is identical for all four cylinders in the engine. Plot requests are not duplicated. Then click on the Paste button in the toolbar and the mouse pointer will become a crosshair icon.. Note that the ducts and junctions have all been numbered sequentially. De-select the Plots toggle button in the Annotations section of the panel (see Figure 2). When finished. Click on the Paste button and place the duplicate network two more times to create four identical duct/junction networks to represent all four engine-cylinders.2 Copying and Pasting the Network The engine-cylinder network. the model should appear as in Figure 3. .Figure 2: Canvas Properties panel This will simply hide the plot icons and not draw them on the canvas. When finished. with the first firing cylinder at crank-angle 0). Change the Firing Order to reflect that of a standard 4cylinder engine – 1. . The default spacing of the cylinder TDCs will be appropriate for this tutorial.. enabling direct access to the Engine General Panel (previously accessed through the Model pull-down menu or an engine cylinder junction) and also allow for right-click selection to add plots and other attachments (sensors and actuators to be discussed in later tutorials). 3. Currently. This panel displays currently entered geometric values from the Engine General Panel.this must be updated to reflect that three new cylinders have been added.Figure 3: Single Cylinder Flow Network Duplicated 1. Change the No. there is only one cylinder in the engine -. of Cylinders text field to 4 and press the Enter key. The Firing Order table will automatically calculate the TDC (top dead center time) for each cylinder based upon the No. Select the Create Engine. option from the Tools pull-down menu to open the Create Engine Panel. This will update the Preview of the engine block on the right as well as the Firing Order table at the bottom. 4. When completed.3 Creating an Engine Block Icon Adding an Engine Block icon to the canvas will provide a clickable and selectable object.. the Create Engine Panel should appear as in Figure 4. 2. of Cylinders value and the Strokes per Cycle selection (TDCs are calculated for even firing intervals and are relative to the previous cylinder. Move the Engine Block icon over to the Engine Cylinders that are currently on the canvas by middle-clicking on the icon and dragging it. They will snap into place on the icon and be associated with the icon from that point on. one at a time. The existing Engine Cylinderjunctions can be "dropped" into the icon by middle-clicking on them. from the menu. it will have four Engine Cylinder junctions created along with it by default.Figure 4: Create Engine Panel Click the OK button to close the panel and note the Engine Block icon that is added to the canvas. and placing them over the cylinder place-holders on the icon. leaving an empty Engine Block icon. if the cylinder junctions are placed 3 grid squares apart.. Default WaveBuild grid spacing is 40/square so. . The bore-spacing of the Engine Block icon can be adjusted by right-clicking on the icon and selecting Appearance. When the Engine Block is created. Left-click each of these newly-created Engine Cylinders one at a time (they will highlight in red) and press the Delkey to delete them. use a spacing of 120 (see Figure 5).. Figure 6: Model with Engine Block Icon . the model should appear as in Figure 6.Figure 5: Engine Block Icon Appearance When completed. AirFilters.1 Placing the Simple Y. Phase 3 . Proceed to Step 2 . and characteristic flow values required for the junction.Save your model Select the Save As. The same will be modeled on the exhaust side.. we will use Simple Y-junctions to connect the intake and exhaust cylinders into one inlet source and one exhaust sink. Complex Y-junctions are more flexible but also require more user-input. There are two different Y-Junctions: Simple and Complex. They are also used to represent arbitrarily-shaped volumes with an aspect ratio inappropriate for modeling by a duct.0\examples\engine\TUT_si\tut_si4. This includes T-Junctions.Joining the Cylinders using a Simple Y-Junction Show SI Tutorial.Joining the Cylinders Using a Simple Y-Junction A simple Y-junction will be used to join all four engine-cylinders together at the intake ports.. Chapter sections Example Input File: 2. Catalytic Converter cones. etc. but must have at least oneconnection.1 Placing the Simple Y-Junctions on the Canvas Y-junctions are used anywhere a volume needs to be modeled that has more than one connection point. option from the File pull-down menu and give the model a new name. .0\examples\engine\TUT_si\tut_si4.\Ricardo\WAVE\8. They are used to define any arbitrary shape desired.2 Defining the Simple YExample Output File: Junctions .wvm. Drag and drop one Simple Y-junction on each side of the engine near the middle.\Ricardo\WAVE\8. such as tut_si4. Exhaust Collectors. The Simple Y-junction is assumed to be spherical in shape and requires minimal input – a diameter defines the volume. For this section of the tutorial.wps 2. 4-Cylinder Model and Sweep Plots in WavePost Step 2 .wvm Junctions on the Canvas 2. The Y-junction is represented by a volume and surface area and can have as many ducts connected as desired. This will represent a large spherical plenum with a single intake pipe that will connect to the existing Intake ambient junction. surface area. vertically (see Figure 1).Converting to a MultiCase. leaving no starting point to draw a duct away from the Y-junction. Enter 50 [mm] for both Left and Right Diameters and 500 [mm] for Overall Length. will occupy that connection point. Enter 50 [mm] for both Left and Right Diameters and 500 [mm] for Overall Length.Figure 1: Simple Y-Junctions on the Canvas Connect the dangling duct ends to the Simple Y-junction by dragging and dropping (use the middle-mouse button) anywhere on the blue portion of the junction. 700 [K] Temperature. Create another new duct between the Simple Y-junction on the exhaust side and the Exhaust ambient (following the Left to Right convention). and 650 [K] Wall Temperature. . . If there are no connection points on a Yjunction and a duct must start at that junction and be drawn away from it (to follow the Left to Right convention). The Discretization Length should be 35 [mm].05 [bar] Pressure. Any duct end dropped onto the blue portion of the junction will create its own connection point automatically. simply left-click on the blue portion and drag a duct away from the Y-junction. the model should appear as in Figure 2. Enter 40 [mm] for the Discretization Length. Create a new duct between the Intake ambient and the Simple Y-junction on the intake side. as used earlier in the single-cylinder model. The default initial conditions are suitable for this duct. Dropping the dangling duct end on the existing connection point. When completed. Appropriate initial conditions for this duct should be set as 1. The default coefficients and initial conditions are suitable for this tutorial (see Figure 3). The geometry for the Y-junction is defined using only a Diameter value. Double-click on the intake-side Y-junction to open the Simple Y-Junction Panel.2 Defining the Simple Y-Junctions The Simple Y-junctions must be fully defined before the model will run. . as the junction is assumed to be spherical in shape.Figure 2: All Ducts Connected 2. Type 50 [mm] in the Diameter text-field. The volume and surface area are therefore easily determinable using the entered Diameter value. We must define the geometry of the junction as well as the orientation for all of the connected ducts. They should be oriented similarly to how they appear on the WaveBuild canvas in Figure 2. thus reducing the number of angles that need to be computed. Once a convention for the X. Once corrected. it is usually easiest to orient the ducts similarly to the appearance on the canvas (if the orientation on the canvas is close to the true orientation). and Z axis. the Openings panel should appear as in Figure 4. For each attached duct. and Z rotations has been established for a junction. assume that rotation in the clockwise direction is positive. Y. For the sake of this tutorial. If possible. all three fields will turn red to indicate the error. When completed. The green sphere represents the volume occupied by the Y-junction. Orient the ducts leading to cylinders 1 and 4 at 60 degrees off the xaxis and the ducts leading to cylinders 2 and 3 at 30degrees off the x-axis. The junction/ducts can be rotated in 3-D space by holding the Shift button while clicking and dragging in the window using the middle mouse button. Y. A new window will open with a graphical representation of the junction and the connected ducts. Although the orientation of each duct is only important relative to the other ducts at the junction. the defined angles are geometrically impossible to orient the duct in 3-D space). You can define the directions of positive and negative rotation and there is no right or wrong way.e. this should be adhered to for all the ducts joined to this junction. If the entered values for these angles do not sum correctly (i. it is often easier to keep one plane flat when dealing with a junction. . the fields will turn green again. based on the duct diameters. The currently-selected duct is colored solid red in the window while the other ducts are drawn in translucent gray. the orientation needs to be given using three angles to describe the duct position relative to the X. relative to the size of the green sphere. while the connected ducts are scaled in size.Figure 3: Intake-side Simple Y-Junction Panel Click on the Edit Openings button to orient the connected ducts. When completed. Temperature of 700 [K]. the Simple Y-junction Panel and Openings panel should appear as in Figure 5 and Figure 6below.Figure 4: Openings Panel for Simple Y-Junction 1 The exhaust-side Simple Y-junction should be set up similarly. as in the intake-side Y-junction. and Wall Temperature of 650 [K]. respectively. The orientation of the ducts should be similar to that of the layout on the canvas. with a Diameter of 50 [mm] and initial conditions similar to the outlet duct – Pressure of 1. .05 [bar]. Figure 5: Exhaust-side Simple Y-Junction Panel . Phase 3 .Creating a Multi-Case Speed Sweep Show SI Tutorial.Figure 6: Openings Panel for Simple Y-Junction 2 Save your model Click on the Save button in the toolbar to save the file. Proceed to Step 3 .Converting to a MultiCase. 4-Cylinder Model and Sweep Plots in WavePost . In this section you will learn how to incorporate multi-case runs into the WAVE engine model. From such runs. WAVE assumes that the value used in the previous case is suitable.1 Adding Cases with the Case Manager Cases can be added and deleted using the Case Manager at the bottom of the WaveBuild canvas. .wvm Example Output File: .1000 for Cases #3 #6.1 Adding Cases with the Case Manager 3. or general behavior between cases can cause WAVE to crash at runtime. Click on the Add Case button 5 times to create 5 more cases for a total of 6 cases. The Constants Panel should appear as in Figure 2. using 1000 rpm increments to simulate multiple steady-state test points in a speed sweep. using light-gray text.) curves of the engine over the range of operation.0\examples\engine\TUT_si\tut_si4. Therefore when in any case other than Case #1. components.\Ricardo\WAVE\8. A popular application is to have multi-case runs that cover the engine RPM range of operation. etc. Also note that the values from Case #1 are filled in for all of the new cases.\Ricardo\WAVE\8. To get useful results from this model.wps 3. respectively. Enter 4000 . you need to set up the run conditions. Volumetric Efficiency. the background of the case text field will be red to warn the user as in Figure 1. we will step from 6000 rpm down to 1000 rpm. one can calibrate or study the Torque (Power.2 Changing Constants between Cases .0\examples\engine\TUT_si\tut_si4. WARNING: It is dangerous to edit the model in any case other than Case #1 as changing the elements. Select the Case #2 field for the SPEED constant and enter 5000.Step 3 . Figure 1: Case Manager when case other than Case #1 is selected Make sure to return to Case #1 before continuing by either typing directly into the text field or using the arrow selection buttons.2 Changing Constants between Cases The convenience of using multiple cases is that Constant values can be changed from case to case. For this tutorial. 3.Creating a Multi-Case Speed Sweep The model is complete. Chapter sections Example Input File: 3. Click OK to close the panel and save the settings. If no new value is provided for a constant. Open the Constants Panel and note that there are now columns added to the table for every new case created. The light-gray text denotes that the value is carried over from the previous case. Enter the values as shown in Figure 4 These profiles describe the temperature of the combustion chamber cooling slightly with a decrease in engine speed. respectively. Intake Valve. Typically. {LINER_TEMP}. with a change in engine speed other parameters change as well. . Click on the Apply button and a message will appear as show in Figure 3. Figure 3: Undefined Constants Message Box WaveBuild has detected that new constants have been used but are not defined in the Constants Panel. and Exhaust Valve temperatures.Figure 2: SPEED values in Constants Panel When running a speed-sweep simulation. Cylinder Head. it is recommended to start at the high speed and move downwards toward the low speed. Click on the Yes button to open the Edit Constants panel and edit the profiles for these five new constants. {IV_TEMP}. Click OK to save these constant profiles and close the Edit Constants panel. thus any problems with the general setup may be detected earlier when starting at a high RPM. This is because the WAVE solver is actually working in a timebase of seconds and the solution tends to converge based on the number of repeated engine cycles. More cycles can be completed at high RPM in a given amount of time in seconds than at low RPM. and {EV_TEMP} in the text fields for the Piston Top. Double-click on the Engine Block icon to open the Engine General Panel. This means a system running a high RPM will tend to finish quicker than at low RPM. Cylinder Liner. Click on the Heat Transfer tab and enter {PISTON_TEMP}. such as combustion behavior and cylinder temperatures. {HEAD_TEMP}. sum Files . Click OK to save these constant profiles and close the Edit Constant panel.out and .Figure 4: Profiles for Combustion Chamber Temperatures Click on the Combustion tab and enter {CA50} in the Location of 50% Burn Point text field and {BDUR} in the Combustion Duration (10-90%) text field. These constants help to describe the shorter crank angle duration of combustion and retarding of spark timing at lower engine speeds. Proceed to Step 4 . Figure 5: Profiles for SI Wiebe Function Inputs Save your model Click on the Save button in the toolbar to save the file and then click on the Run Screen Mode button to launch the analysis (note how engine cycles take longer to complete in the later cases. Click the OK button to close the Engine General Panel. Click on the Apply button again to be queried on adding these constants to the table.Changes in the . at lower engine speeds). Select Yes from the Query window and enter the profiles as given in Figure 5. 0 0.00 0.00 0.out file created by the run. We will open both files and observe what is different from the single-cylinder output.2 Changes in the .544 376.sum File Example Output File: . This practice usually saves the simulation a few engine-cycles in each case as it is initialized using conditions that are most-likely closer to the converged results than those specified by the user when setting up the simulation.Show SI Tutorial.00 0.00 0.914 0.013 TCYL 301. Then.sum Files With a multi-case. note the warning statement: W*** FLOW FIELD NOT REINITIALIZED AT START OF THIS CASE This warning tells us that the initial conditions for Case #2 are set by using the final conditions from Case #1 (controlled by the Reinitialize Flowfield Between Cases toggle button on the General Parameters Panel).0\examples\engine\TUT_si\tut_si4.000 ENG: 1 1 786 66. 4-Cylinder Gasoline Engine at 6000 rpm NC ICYC ISTEP AIR-KG/HR VOLEF TEXH PHI IMEP PMEP ENG: 1 0 1 0.Changes in the .0000 0.000 ENG VOLEF(TOT) = 0.2 403.2 FTR 0. note that the simulation initializes by running an engine-cycle 0 only for cylinder 1. Phase 3 .1 Changes in the .00 0.628E 0.000 ENG: 3 1 362 0.597E 0.893 -1.Converting to a MultiCase.893 IHP 0.0000 PHI(1) = 0.497 1. 4-Cylinder Model and Sweep Plots in WavePost Step 4 . First.00 ISFC 0.000 900. there are some changes in the .000 ENG: 2 1 182 0.wvm 4.569 1.84 -2.0 0.2 0.out files of note.000 0.00 0.sum and .00 0.021 ENG VOLEF(TOT) = 0.2 0.1 Changes in the . For the six cases .000 900.000 900.00 0.0000 0.wps 4.000 0.out and .2470 1.806 437.5 405. open the .0\examples\engine\TUT_si\tut_si4.0 0.000 0.492 0. for every engine-cycle following.0000 -2.000 ENG: 4 1 554 0.9 403.080 -1. Chapter sections 4.000 0. Note that there is no engine cycle 0 for cylinder 1 in any of the cases following Case #1 since no re-initialization occurs.35 0.\Ricardo\WAVE\8. 4-cylinder model.0000 PCYL 1.869 0. run is created for each case in the multi-case run.2015 PHI(1) = 0.613E Also note that the same output created for the single-cylinder.000 0.000 900.out File Example Input File: .out File Using your favorite text-editor.614 1.0 0.\Ricardo\WAVE\8. data for each cylinder in the 4-cylinder engine is printed: TITLE: SI Tutorial. At the beginning of the output for Case #2.338E 0. Creating Sweep Plots in WavePost The output files created by WAVE for use in WavePost (the . 4-Cylinder Gasoline Engine at 5000 rpm Proceed to Step 5 . while the start of a new case results set is delimited by a CASE: line and followed by a TITLE line as below (note that the {SPEED} constant in the title is updated for every case): # CASE: 2 ----------------------------------------------------------------------------------------------------TITLE= SI Tutorial. 4-Cylinder Model and Sweep Plots in WavePost Step 5 .wvd files) now contain information about the simulation for all six cases in the model.sum File Open the .Creating Sweep Plots in WavePost Show SI Tutorial.in this simulation. Phase 3 . showing that a total of 10 (35 .sum file with a text-editor and note that there is a set of cycle-averaged summary outputs for every case in the simulation.0\examples\engine\TUT_si\tut_si4.wvm .\Ricardo\WAVE\8. Chapter sections 5. the reduction in the number of cycles is noted in the table below. The end of a case results set is delimited by a # sign. Sweep Plots can be created in WavePost to illustrate change in output values over the speed range of the model.25 = 10) fewer engine-cycles are performed if reinitialization is skipped in this manner: NUMBER OF CYCLES REQUIRED Case # Reinitialized Flowfield Non-reinitialized Flowfield 1 5 5 2 5 3 3 5 4 4 5 4 5 7 5 6 8 4 Total 35 25 4.sum and .2 Changes in the .Converting to a MultiCase.1 Multi-case Handling in Example Input File: . then the plots can be filtered by case number. Selecting a case in this way will also change the behavior of displayed results. Manually-created Time Plots and cycle-averaged results or animations (discussed in Phase 4) will display results from the selected case. In a run with a small number of cases. Check the Show selected case box above the Plots folder tree. 2.\Ricardo\WAVE\8.1 Multi-case Handling in WavePost Launch WavePost from WaveBuild by left-clicking in the Launch WavePost button in the WaveBuild toolbar . If there are too many plots listed to make this practical. this will enable the filtering by case number.wps file with the Time Plots folder opened in the Plots folder tree (see Figure 1). Figure 1: WavePost Plot Tree There are two ways to distinguish which plot is from which case: 1. it's easy to pick out the correct plot. from Case #1 upwards. By default. .2 Creating Sweep Plots Example Output File: . are named by the plot type. from plot requests in WaveBuild. This will filter the plots and only display those with data from the selected case (see Figure 2).0\examples\engine\TUT_si\tut_si4. Hence similar plots from different cases have the exact same name. expand the results file list in the Results File folder tree and select the desired case by left-clicking on the case icon .WavePost 5. WavePost opens a . The plots are listed in order of case. Then.wps 5. This can be confusing when trying to select the plot from a specific case. All plots that have been created by default. Figure 2: Filtering Plots by Case 5.2 Creating Sweep Plots Sweep Plots are plots of cycle-averaged results from all cases in the analysis, using output found in the .sum file. Using the results from our multi-case analysis, which simulates the engine over the range of operating speeds from 6000 down to 1000 rpm, we can create plots of any output parameter found in the .sum file (e.g. torque, power, etc.) vs. engine speed or against any other desired parameter. To create a sweep plot, right-click on the Sweep Plots folder in the Plots Frame and select the Add Sweep Plot -> 2D Plot... menu items (see Figure 3). Figure 3: Creating a New Sweep Plot This will create a new Sweep Plot named Sweep Plot #1 by default. The plot is empty, with no data displayed. To add data, select the Add pull-down menu and then select the Data... menu item to open the Sweep Data Panel. This contains a list of all of the keywords in the .sum file that correspond with a cycle-averaged numeric value. The list defining .sum file keywords and their associated units is available in the WAVE Help section. Selectbhp for the Dependant Variable (Y) and select rpm for the Independent Variable (X). The Sweep Data Panel should appear as in Figure 4 when completed. Click the OK button to apply. Figure 4: Sweep Data Panel WavePost will automatically label the axes (with units) by the .sum variables selected and name the curve by the filename and keyword selected. Double-click on the axes or the curve to edit these names. Double-click on the title and edit the name to Power vs. Engine Speed. A different (but compatible by conversion) units system can be selected for the axis so that users can choose how data is displayed without doing clumsy numerical conversions manually. When completed, the plot should appear similar to Figure 5. Figure 5: Power vs. Engine Speed WavePost can also easily create Default Sweep Plots, where a summary quantity from an element in the model can be plotted against a default X-Axis. The default X-Axis used can easily be set by expanding the Defaults sub-folder under the Sweep Plots folder – the first branch of the expanded tree is the X-Axis Settings. Double-clicking on this branch will open the Default Sweep Plot X-Axis Panel, as shown below in Figure 6. Figure 6: Default Sweep Plot Setting If an engine exists in the model, "RPM" will be selected by default. Alternatively, you can select "Case" or "Cycle" ("Time" is allowed in a non-cyclic run). Otherwise, you can also select any other summary quantity by selecting the "Custom" option. Click the "OK" button to close the panel. Right click on the engine block icon and create a sweep plot of torque (Add Sweep Plot > Performance > Brake Torque vs. > RPM). The sweep plot will open and be added to the plots in the results tree. Use this method to create a plot of volumetric efficiency as well. The completed plots should appear as in Figures 7 and 8. Figure 7: Torque vs. Engine Speed Save your file . Engine Speed Figure 8: Volumetric Efficiency vs. Each part of the system will be discussed and modeling practices examined. our model will have a complete air induction system that is representative of a real engine. ..wvm.tut_si4. All of these parts will be modeled in WaveBuild to create the induction system with appropriate restrictions.0\examples\engine\TUT_si\tut_si4_intake.Adding the Intake System and Creating Animations in WavePost Show SI Tutorial. is re-run. Proceed to Phase 4 . air cleaner with filter.wps.wvm Example Input File: .wps session file under a new name. Phase 4 . throttle body. Animations will be created in WavePost for reporting and data analysis. and intake manifold. such as Comparison. Phase 4 Steps Optional Starting Point: 1 The Snorkel and Zip Tube 2 The Air Cleaner with Filter 3 The Throttle Body 4 The Intake Manifold 5 Creating Animations in WavePost .0\examples\engine\TUT_si\tut_si4_intake.Adding the Intake System and Creating Animations in WavePost The Intake or Induction system consists of a snorkel. option to save the .\Ricardo\WAVE\8.wps With these five steps.0\examples\engine\TUT_si\tut_si4.. so that it won't be overwritten by WAVE in the event that the model file.wvm Example Output File: .Click on the File pull-down menu and select the Save As. zip tube.\Ricardo\WAVE\8.\Ricardo\WAVE\8. zip tube. consists of a snorkel. Phase 4 . We will skip over the air cleaner in this step and return to model it in step 2. The snorkel and zip tube can be easily modeled with just ducts and orifice junctions. so it is easiest to draw them on the canvas first.Show SI Tutorial.Adding the Intake System and Creating Animations in WavePost Step 1 . leading up to the intake manifold. .The Snorkel and Zip Tube The intake sub-system. air cleaner. and throttle body. 1 Detaching the Intake Ambient Junction 1. The 4-cylinder model as created has all four intake ports joined together at a single Simple Yjunction. These will eventually be attached to the ends of the runners from the intake manifold.wps 1. This will leave all four intake port ducts dangling with no junction to attach to upstream (see Figure 1). Figure 1: Y-Junction and Upstream Duct Deleted Click and hold the middle mouse button to move the ambient junction named Intake down to the bottom of the canvas.\Ricardo\WAVE\8.3 Defining the Ducts (Tapered and Bent) . This will serve as the starting point for the induction system. .wvm Example Output File: .0\examples\engine\TUT_si\tut_si4_intake.2 Placing the Required Orifice Junctions and Ducts 1. For now.Chapter sections Example Input File: 1. The intake ambient junction will be re-used upstream of the induction system as the atmospheric conditions before the snorkel. they can remain unattached.1 Detaching the Intake Ambient Junction Before performing any actions make sure the model is in Case #1. Highlight both the intake-side Simple Y-junction and upstream duct (holding down the shift key and left-clicking) and hit the Delete key. but the Y-junction and duct created for the 4-cylinder model can be selected and deleted.0\examples\engine\TUT_si\tut_si4_intake.\Ricardo\WAVE\8. .2 Placing the Required Orifice Junctions and Ducts The snorkel and zip tube can easily be modeled using only orifice junctions and ducts. Figure 2: Snorkel and Zip Tube Schematic Place orifice junctions and connect with ducts as shown in Figure 3.1. place two Complex Y-junctions and connect with a duct. A schematic of the system with required dimensions is shown in Figure 2. Remember to follow the Left to Right convention when creating the ducts. In place of the air cleaner. right-click on the duct and select Add Control Point from the menu: A control point can be selected with the middle mouse button and moved to make the duct appear bent (it will snap to grid points just like junctions do).3 Defining the Ducts (Tapered and Bent) . Figure 4: Control Points to Draw Bent Duct 1. Using two control points diagonal from each other by one grid square will create the appearance of a smooth 90° bend. Multiple control points can be added to a duct.Figure 3: Flow Network To make the last duct in the zip tube (duct22 in Figure 3) appear bent on the screen. as shown in Figure 4. Flow will always be contracting and therefore the slightly high taper angle is not of concern. Read this sidebar on modeling tapered ducts and note that we are modeling upstream of the intake manifold. and 300 [K] for Initial Fluid and Wall Temperatures. Figure 5: High Taper Angle Also note that when entering dimensions for the last duct in the zip tube. . indicating a warning that the calculated taper angle of11. the Taper Angle field turns yellow.3099° is outside of the recommended range for this parameter (see Figure 5). with Overall Length of 50 [mm]. thus expect constant flow into the engine. The Bend Angle field on the Dimensions tab of the Duct Panel allows the user to specify how much of a bend occurs across the entire length of the duct. above. Remember to use 35 [mm] for the Discretization Length for all ducts in the intake system and set initial conditions to be 1 [bar] Pressure. The pressure drop due to this bend is also then distributed across the entire length of the duct.Using the schematic from Figure 2. edit the ducts representing the snorkel and zip tube and enter the appropriate Diameters and Lengths (leave the Complex Y-junctions and duct between them for later). the 90° Bend Angle should be included (see Figure 6). Note that when setting the Left Diameter of the first duct to 70 [mm] and the Right Diameter to 50 [mm]. If you would like to specify your own Cp value. simply set the Bend Angle to 0° and set the Pressure Loss coefficient on the Coefficients tab. The Cp value is then divided evenly amongst the number of elements in the duct and then the pressure loss in each element is calculated by: When completed. the WAVE solver uses this Bend Angle. NOTE: The Cp values calculated by the bend angle and entered in the Coefficients tab will be added together if they are both specified! . the intake subsystem should appear as in Figure 7. the average Diameter of the duct.Internally. and the duct Overall Length to calculate a Cp value based on simple equations (see the WAVE Help section on ducts for more details). Figure 7: Intake Subsystem Save your model Select the Save As. Phase 4 . Proceed to Step 2 .The Air Cleaner with Filter Show SI Tutorial. we will define these junctions and duct to appropriately represent the physics of the system in WAVE.The Air Cleaner with Filter In the last step.. In this step.Adding the Intake System and Creating Animations in WavePost Step 2 . two Complex Y-junctions were placed on the canvas with a duct connecting them to represent the air cleaner and filter. option from the File pull-down menu and give the model a new name. such as tut_si4_intake. . Saving this file and running it with a different name will allow comparison of results to the models built and analyzed earlier..wvm. \Ricardo\WAVE\8. a filter is modeled as an orifice that approximates the pressure drop of the real system. Acoustic simulations should model the air cleaner volumes in smaller sub-sections and the filter with numerous perforates! Chapter sections Example Input File: 2. Typically.\Ricardo\WAVE\8. It is impossible to appropriately model the filter passages true to life as flow through a fibrous filter is very non-one-dimensional.1 Defining the Complex Y-Junctions A schematic of the air cleaner geometry is shown in Figure 1.wps 2.wvm Example Output File: .1 Defining the Complex YJunctions 2. It is simply two cylindrical volumes separated by a flat.0\examples\engine\TUT_si\tut_si4_intake. the two Complex Y-junctions will represent the two cylindrical volumes and the duct connecting them will represent the filter. Figure 1: Airbox Schematic For our model. circular filter.0\examples\engine\TUT_si\tut_si4_intake. Double-click on yjun1 and enter the appropriate values as given in Figure 2. .2 Representing the Filter as a Massless Duct .NOTE: This modeling method is only appropriate for performance simulations. and Thick. is the distance from the duct connection point across the volume. sometimes referred to as the characteristic length. DELX. See Figure 3 for a diagram of the DELX values for both Complex Yjunctions. Ducts are oriented similarly as on the Simple Y-junction.allowing the user to enter their own value is what makes the Complex Y-junction flexible)! Click on the Edit Openings button to orient the connected ducts. DIAB. Clicking on either of these will assume a spherical shape and calculate Volume or Heat Transfer/Skin Friction Area accordingly from the Diameter value (this is identical to using a Simple Y-junction -.Figure 2: Airbox Network Representation  Note the auto-calculator buttons provided for both Volume and Heat Transfer/Skin Friction Area fields. Note the new fields for each connected duct: DELX. The orientation of duct19 and duct20 should be used as shown in Figure 1. . perpendicular to the duct entrance.Figure 3: DELX Values DIAB. Figure 4: DIAB Values for duct20 and duct21 . is the equivalent diameter for the maximum area that the gas can expand into. See Figures 4 and 5 for diagrams for the DIAB values for both Complex Y-junctions. sometimes referred to as the expansion diameter. It is not necessary to set this value in performance simulations as it has no effect whatsoever on the outcome. the orientations for the Complex Y-junctions should appear as shown in Figures 6 and 7. When completed.Figure 5: DIAB Value for duct19 Thick is the orifice thickness and is used in acoustics simulations to calculate the acoustic end correction. Figure 6: Orientation Panel for 1st Complex Y-Junction . Figure 7: Orientation Panel for 2nd Complex Y-Junction 2. No other parameters need be set. . When completed.37 [mm] provides for a 1.0\examples\engine\TUT_si\Air_Filter_Calibration In this case.25 kPa pressure drop across the system at a flow rate of 280 kg/hr. Varying the orifice diameter will produce different mass flow rates and we can target the desired flow rate with the prescribed pressure drop. near the maximum expected mass flow rate). see: . the orifice diameter of 140.\Ricardo\WAVE\8. Typical information provided for an air filter is a pressure drop achieved at a given mass flow rate (most frequently. the massless Duct Panel should appear as in Figure 8. For our air filter.2 Representing the Filter as a Massless Duct The filter will be modeled as a massless duct (overall length of 0) and will act like an orifice plate between the two volumes by having a smaller diameter than the surrounding volumes. Massless ducts need only to have Left and Right Diameters defined (these must be equal!) and the Overall Length should be set to 0.25 kPa pressure drop at 280 kg/hr mass flow of air. The Diameter of duct20 can be obtained by steady-state flow simulation with a fixed pressure drop by putting ambient junctions at either end of the system and running a 1second time-based simulation. we are supplied with the information the filter creates a 1. To understand this setup. Phase 4 .The Throttle Body Show SI Tutorial. we will add a throttle body. this common practice allows for the engine load to be varied between cases by changing the open area of the throttle body.Figure 8: Massless Duct Panel Save your model Click on the Save button in the toolbar to save the file. . Although this tutorial won't do so. Proceed to Step 3 . represented as an orifice containing a butterfly valve.Adding the Intake System and Creating Animations in WavePost Step 3 .The Throttle Body In this step. 0\examples\engine\TUT_si\tut_si4_intake. starting with the final orifice junction of the zip tube.\Ricardo\WAVE\8. In WaveBuild.wps 3.3 Using the Throttle Valve Junction . Figure 1: Throttle Body Schematic Place the required junctions on the canvas and connect with ducts as shown in Figure 2.Chapter sections Example Input File: 3.2 Defining the Butterfly Valve 3. Edit both ducts to have Overall Lengths of 50 [mm] and constant Diameters of 60[mm]. . Remember to set the Discretization Length to 35 [mm] and the Initial Conditions to the standard of 1 [bar] Pressure and 300 [K] Initial Fluid and Wall Temperatures.\Ricardo\WAVE\8.1 The Basic Geometry The schematic of the throttle body geometry is shown in Figure 1. we will model this geometry as two ducts connected in the middle using a throttle valve junction.wvm Example Output File: . The throttle valve junction will represent the throttle blade.0\examples\engine\TUT_si\tut_si4_intake.1 The Basic Geometry 3. In order to use it.2 Defining the Butterfly Valve The throttle valve junction represents an instance of a butterfly valve type. the Butterfly Valve Editor panel should appear as in Figure 3. When completed. then click on the OK button to open the Butterfly Valve Editor panel. with a Minimum Plate Angle (angle at which the valve sits effectively closed) of 5 [deg]. Click on the Add button in the Valve List and select the Butterfly valve type.Figure 2: WaveBuild Throttle Body 3. The Calculated Values section of the panel will allow you to preview the calculated geometric quantities. as defined in the Model > Valves… list. we must first define the butterfly valve. Set the Bore Diameter to 60 [mm] and the Shaft Diameter to 5 [mm]. Click on the Valves… menu item in the Model pull-down menu. Figure 3: Butterfly Valve Editor . Use the slider bar to observe the schematic and values as the butterfly valve angle changes. With the Forward/Reverse coefficient profile type radio button selected. Select Valve Number 3 from the pull-down list and set the Plate Angle to{THROTTLE_ANGLE} (see Figure 5). so it can change between cases.22 deg. This parameterizes the throttle plate angle. If you have a defined profile as a function of angle. allowing a full sweep of realistic coefficient values from when the valve is closed until it is fully open. allowing us to set the angle in the Constants Panel. giving load control during the simulation. click on the Edit Flow Coefficient Profiles button to open the flow coefficient profile editor panel. . For the purposes of this simulation we will define a coefficient of 0. When completed. Figure 4: Throttle Discharge Coefficients 3.5 at 5 deg and 1 at 85. it should be entered here. the flow coefficient profile editor should appear as in Figure 4.3 Using the Throttle Valve Junction Double-click on the throttle valve junction on the canvas to open the Throttle Valve Junction Panel and edit the ID of the junction to THROTTLE. .Figure 5: Throttle Valve Junction Panel The background of the Plate Angle field will turn yellow as the constant THROTTLE_ANGLE is not yet defined. when queried about adding the constant to the constants table. the intake subsystem should appear as shown in Figure 7. Modeling the throttle fully open assumes we are running a full-load speed sweep. click the OK button again and set the value 90 for all cases (setting it in Case #1 only is sufficient. Figure 6: Throttle Valve Constant When completed. see Figure 6). Click the OK button to save the settings and close the panel and. Proceed to Step 4 .Adding the Intake System and Creating Animations in .The Intake Manifold Show SI Tutorial.Figure 7: Completed Intake Subsystem Save your model Click on the Save button in the toolbar to save the file. Phase 4 . The techniques for modeling a large volume with sub-volumes and for modeling a tapered duct (bellmouth entry to intake runners) will be demonstrated.1 The Basic Geometry The schematic of the intake manifold geometry is shown in Figure 1. . Four Complex Y-junctions will be attached together using massless ducts to represent the plenum volume.\Ricardo\WAVE\8.wvm Example Output File: . we will model the inlet pipe as a single duct.1 The Basic Geometry 4.3 Modeling the Intake Runners . to model the bellmouth entry. we will model the simple log-plenum intake manifold using more complex yjunctions. Chapter sections Example Input File: 4.WavePost Step 4 . A discharge coefficient will be imposed for incoming flow to the first runner duct.\Ricardo\WAVE\8. The plenum will be simplified and assumed cylindrical in shape (with an equivalent diameter of 110 mm). In WaveBuild.0\examples\engine\TUT_si\tut_si4_intake.2 Modeling the Plenum SubVolumes 4.The Intake Manifold In this step. Three ducts will be used to represent each intake runner.wps 4.0\examples\engine\TUT_si\tut_si4_intake. They will appear gray on the canvas. . Remember to set the Discretization Length to 35 [mm] and the Initial Conditions to1. indicating they are massless ducts. Drag and drop the required orifice and y-junction elements onto the canvas from the Elements Tree and connect them with ducts accordingly.0 [bar] Pressure and 300 [K] InitialFluid and Wall Temperatures. Remember to follow the Left to Right convention. Figure 2: WaveBuild Intake Manifold 4. The Y-junctions have an equivalent diameter of 110 mm. The Left and Right Diameters of the massless ducts should equal the equivalent diameter of the Yjunctions (which will also match the DIAB values assigned to the connections) so that there is no pressure loss due to expansion or contraction. Assign Left and Right Diameters of 60 [mm] and an Overall Length of 150 [mm]. Use four Complex Y-junctions to model the intake manifold plenum.2 Modeling the Plenum Sub-Volumes Edit the duct representing the inlet to the intake manifold. Start the inlet pipe of the intake manifold at the last orifice junction of the throttle body.Figure 1: Intake Manifold Schematic The equivalent network as created in WaveBuild is shown in Figure 2. These four Y-junctions will be connected using massless ducts (zero overall length). so assign Left and Right Diameters of 110 [mm] to the massless ducts. along with 0 [mm] Overall Lengths (see Figure 3). Figure 3: Massless Duct between Plenum Sub-Volumes The Y-junctions should be edited to have Diameter values of 110 [mm]. .0 L divided evenly by four). Volume values of 0. and Heat Transfer/Skin Friction Area values of approximately 27300 [mm2] (pi*diameter*length) as in Figure 4.75e+006 [mm3] (3. the DIAB value should be calculated from the maximum area the gas can expand into along the length of the single y-junction into which the duct enters. . The DELX values for the massless duct connections should be 79 [mm] (the length of each subvolume in the direction of flow through the massless ducts) and the DIAB values should be 110 [mm] (equal to the massless duct Diameters so no expansion or contraction occurs). See Figure 5 for a representative duct orientation.Figure 4: Y-Junctions Representing Plenum Sub-Volumes Orient the duct connections according to the layout on the screen (see Figure 2). Thus DIAB is approximately 105 [mm]. Should the area used to calculate the DIAB value for each runner connection be the maximum area the gas can expand into in the Y-junction or the length of the entire plenum? Technically. This is because any losses caused by flow traveling along the length of the plenum will be accounted for by mass transfer from one y-junction to the next. The DIAB values for the runner connections require some thought. For our geometry. the maximum area for expansion in the direction of flow from the runners is equal to 110 mm * 79 mm 4 = 8690 mm 2. The DELX values for the runner connections should be 110 [mm] (distance across the subvolume in the direction of flow into the runners). the pressure and flow after a sudden expansion has a greatly diminished response the larger the expansion is. Once the DIAB value is approximately twice the diameter of the entering duct.Figure 5: Duct Orientation for First Plenum Sub-Volume Note. Figure 6 illustrates this effect. Figure 6: DIAB Sensitivity Illustration . the effect of the expansion changes very little with further increase in DIAB. context menu option will open the Parameters Panel. multiple-select the items to be edited by holding the shift key and left-clicking on the items or by drawing a box around the desired items while holding down the left mouse button. menu option. in combination with ducts if desired). Edit the ducts to have the geometry represented in the schematic and remember to set the Discretization Length to 35 [mm] and theInitial Conditions to 1 [bar] Pressure and 300 [K] Initial Fluid and Wall Temperatures. This will open the Duct Template Panel (since all selected elements are ducts) allowing fields to be set for multiple ducts simultaneously (see Figure 7 for example of setting duct geometry for all runner ducts).. the Edit Parameters. With the desired ducts selected (highlighted in red) right-click on the white background of the canvas and select the Edit Parameters. if the orifice elements between the ducts are also selected). Figure 7: Duct Panel for setting parameters in all Runner Ducts If more than just ducts are selected (e..4. regardless of whether or not they are the same element type (see Figure 8 for example of setting duct geometry for all runner ducts).. Only the edited input fields will be set for all selected ducts. which allows you to set input values for multiple elements at once.3 Modeling the Intake Runners Each runner. as shown in the schematic (see Figure 1).. To edit multiple ducts at the same time (junctions can also be edited in this manner. will be represented by three ducts. The middle duct for each runner should have a 45° Bend Angle.g. . in the range of 0. from the runner duct to the plenum Y-junction. This creates a Taper Angle of approximately 8. To accurately represent the effect of the bellmouth entry. no one item's given value will show up in the entry fields – they will be zero by default. This indicates that flow will most likely separate from the duct wall during reverse flow. . it will experience a sudden expansion into the junction and the loss will be accounted for. The zero value will not be written to the items unless the checkbox is selected (or the number zero is typed into the field). the Disch. Moreover.Figure 8: Edit Parameters Panel for setting parameters in all Runner Ducts The checkbox next to each entry indicates whether the value will be written to each item. from the valve towards the plenum.95 1. This means that during reverse flow. and a sudden expansion will occur creating a pressure loss. both ends (Left and Right) of the first runner duct should have Diameter values of 40 [mm]. Since multiple items are selected. from the plenum junction to the runner duct should be set to a representative high value.5°.0 in the Openings panel for each Y-junction (see Figure 9). higher than the recommended limit of 7° as discussed in this sidebar on Modeling Tapered Ducts. Coef. the actual geometry doesn't have a constant taper – it has a bellmouth entry (which has a rapid change in cross-sectional area) at the beginning and then a gentle taper towards the duct end. The first duct is shown in the schematic to have an entry (Left end) Diameter of 70 [mm] and an exit (Right end) Diameter of 40 [mm]. To account for this physical phenomenon. the entire model should appear similar to Figure 10.Figure 9: Setting the Discharge Coefficient to 0. Figure 10: Completed Model with Intake System Save your model Click on the Save button in the toolbar to save the file. use control points on the middle runner ducts to represent the Bend Angle. If desired.Adding the Intake System and Creating Animations in WavePost Step 5 . Proceed to Step 5 . Phase 4 . When completed.Creating Animations in WavePost Show SI Tutorial.Creating Animations in WavePost .99 Connect the ends of the intake runners to the dangling port duct ends using a simple orifice junction. 1 Requesting Animation Data in WaveBuild In WaveBuild.mpg format 5. Run the WAVE model by clicking on the Run Screen Mode button in the toolbar (if prompted to save the model before running WAVE.wvm WaveBuild 5. open the Output and Plotting Panel by selecting the Output and Plotting.wps Example Output File: File 5. item from the Simulation pull-down menu. Check the Generate Animation Data checkbox and click OK to save the setting and close the panel (see Figure 1).1 Requesting Animation Data in . These animations can be viewed in WavePost and then saved as MPEG files for use in presentations and reports.3 Creating and Saving Animations . Chapter sections Example Input File: 5..\Ricardo\WAVE\8.2 Adding Results to an Existing . Figure 1: Requesting Animation Data .WavePost can use time-based data to animate the network with color contours of basic datasets..wps in .0\examples\engine\TUT_si\tut_si4_intake.\Ricardo\WAVE\8.0\examples\engine\TUT_si\tut_si4_intake. click the OK button to save and run sequentially). wvd file for the WAVE model containing the intake system.wvd and .sum files (if matching data exists in the new files). click the Open File button in the toolbar and open the .wps file created in Phase 3.sum files for this WAVE run will be added to the Output Files list (see Figure 2 below). Figure 2: WavePost Output Files Frame Figure 3: Query to Add Data to Existing Plots .2 Adding Results to an Existing . This will open the . without the intake system added on.5.wps file named similarly to the . It should contain sweep plots created during the previous phase of torque.wps. The .wps File Launch WavePost from WaveBuild by left-clicking in the Launch WavePost button in the WaveBuild toolbar . A Query window will pop-up prompting whether to add curves to the existing plots using this file (see Figure 3). power.wvm file currently loaded in WaveBuild. Once WavePost is open. Click on the Add button at the bottom of the Output Files frame and select the newly created . etc.wvd and . This WavePost session file is currently only referencing results from the last model created. Click on the Yes button and every existing plot will add data from the newly added. Open the Sweep Plots to view the comparison of the performance parameters as in Figure 4. Comparison. context menu item. .Figure 4: Data Automatically Added to Power Plot Note that addition of the intake system has changed the predicted performance results. change the name to SI4 Intake Case #1 Velocity. and bends that were added in the intake system. When complete. This will open the Animation Panel and will automatically redraw the model canvas to display the flow network as a simple scaled model. and select the Velocityvariable from the list. below. the Animation panel should appear as in Figure 5. In the Results Frame in the lower left corner of WavePost. Finally. The positive tuning effects are more powerful than the losses due to friction. right-click on the Animation folder under the Network Displays folder and select the Add Animation Display. Check the Crank Animation checkbox to display the cylinder #1 crank animation in the upper right hand corner of the canvas. Use the file browser folder button to select the tut_si4_intake. expansion and contraction. 5.wvd results file.mpg Format Animations can be created using time data stored in the .. type 2 in the Crank Angle field and hit the Enter key (this will update the Time and Number of Frames fields automatically) to create animation steps of 2 crank angle degrees. Power is decreased near 3000 rpm.wvd file. the ducts and junctions are redrawn with relative diameters displayed and color contours to represent the selected variable. but increased above 4000 rpm.3 Creating and Saving Animations in .. WavePost will automatically scale the animation to use the global minimum and maximum values for the variable found over the entire course of the animation. . Uncheck the AUTO boxes and set the Minimum to -20 and the Maximum to 180 and then set the Number of Interval Labels to 11... This may not represent what we want to observe.Figure 5: Completed Animation Panel Click the OK button to close the panel. When completed. the Contour Map Panel should appear as in Figure 6. so we will manually set the range. button on the Animation Panel). This allows you to edit the range and display of the color contours as drawn on the canvas. double click on the contour bar at the bottom of the canvas to open the Contour Map Panel (this can also be accessed via the Contour Map Settings. Now. a file with the name as given above will be created in the working directory. you can record the animation to an MPEG file. This will take a while to complete. Click on the OK button and a progress bar will pop up to show the progress of the rendering process. Click on the record button to open the Movie Recordings Settings Panel. Figure 7: The Movie Recordings Settings Panel When finished. If desired.mpg) and set the MPEG Quality to High (this will use more disk space but create a clearer image) as in Figure 7. Enter a name for the movie in the File text field (Velocity.Figure 6: Completed Contour Map Panel Use the buttons on the WavePost toolbar to play the animation. . It should appear similar to the animation below (right-click on the animation and select Play to repeat). resonator (concentric-tube silencer).0\examples\engine\TUT_si\tut_si4_exhaust. Each part of the system will be discussed and modeling practices examined. .wvm ExampleOutput File: .0\examples\engine\TUT_si\tut_si4_intake.0\examples\engine\TUT_si\tut_si4_exhaust. our model will have a complete exhaust system that is representative of a real engine.Adding the Exhaust System and Creating Spatial Plots in WavePost The exhaust system consists of an exhaust manifold. close-coupled catalytic converter.wps file. Phase 5 Steps Optional Starting Point: 1 The Exhaust Manifold 2 The Catalytic Converter 3 The Resonator (Silencer) 4 The Complex Muffler 5 Creating Spatial Plots in WavePost . Proceed to Phase 5 .\Ricardo\WAVE\8.Adding the Exhaust System and Creating Spatial Plots in WavePost Sample Animation Show SI Tutorial. and flow-reversal style muffler.wps With these five steps.\Ricardo\WAVE\8.Save your file Click on the Save button in the toolbar to save the updated Comparison.\Ricardo\WAVE\8. All of these parts will be modeled in WaveBuild to create the exhaust system with appropriate restrictions. Spatial Plots will be created in WavePost for reporting and data analysis.wvm Example Input File: . Phase 5 . 0\examples\engine\TUT_si\tut_si4_exhaust.Show SI Tutorial.wvm Junction 1.1 Detaching the Exhaust Ambient . The manifold can easily be created using techniques learned while modeling the intake system.2 The Basic Example Output File: Geometry 1. Phase 5 .1 Detaching the Exhaust Ambient Junction .Adding the Exhaust System and Creating Spatial Plots in WavePost Step 1 .The Exhaust Manifold The exhaust manifold consists of runners with a simple 4-1 collector. Chapter sections Example Input File: 1.wps Catalyst Connection 1.\Ricardo\WAVE\8.\Ricardo\WAVE\8.0\examples\engine\TUT_si\tut_si4_exhaust. The collector is attached directly to a close-coupled catalytic converter (modeled in Step 2).3 Defining the Collector and . It can be easily modeled as three ducts representing each exhaust runner (connected by orifice junctions) and a Complex Yjunction representing the collector. and DELX/DIAB settings. but a Complex Y-junction should be used as it is more flexible for tuning purposes (Simple Y-junctions are rarely used in real modeling!). The collector is approximately spherical in shape. but the Y-junction and duct created for the 4-cylinder model can be selected and deleted. The ambient junction named Exhaust will be re-used downstream of the exhaust system as the atmospheric conditions after the complex muffler. Highlight both the exhaustside Simple Y-junction and downstream duct (holding down the Shift key and left-clicking) and hit the Delete key.Before performing any actions. These will eventually be attached to the ends of the runners from the exhaust manifold. The 4-cylinder model with the intake system still has all four exhaust ports joined together at a single Simple Y-junction. 1. . Figure 1: Y-Junction and Downstream Duct Deleted Middle-click and drag the ambient junction named Exhaust down to the bottom of the canvas. This will serve as the end point for the exhaust system. This will leave all four exhaust port ducts dangling (see Figure 1). make sure the model is in Case #1. Heat Transfer/Skin Friction Area. It is extremely simple to make a Complex Y-junction behave exactly like a Simple Y-junction by using all of the defaults for Volume.2 The Basic Geometry The schematic of the exhaust manifold is shown in Figure 2. Figure 2: Exhaust manifold schematic Using the Elements Tree. Remember to create a hanging duct leaving the collector Y-junction to represent the connection with the close-coupled catalytic converter. place all of the required junctions and then draw the required ducts as shown in Figure 3. Connect the dangling ducts from the exhaust ports to the newly created orifice junctions. . 1. Assign similar initial conditions as the runners.3 Defining the Collector and Catalyst Connection The hanging duct that will be connected to the close-coupled catalytic converter can be assigned Left and Right Diameters of 76 [mm] and an Overall Length of 0 [mm] (i. The Wall Temperature of the collector should be higher than the runners. . This will approximately model a direct connection between the collector volume and the entry to the catalytic converter.e. but use a Wall Temperature of 900 [K]. and Wall Temperature of 750 [K]. Define the Y-junction representing the collector using the values shown in the schematic. it is a massless duct).Figure 3: Exhaust manifold flow elements in WaveBuild Define all the ducts using the values shown in the schematic. Fluid Temperature of 1100 [K]. When completed. Remember to use 40 [mm] for the Discretization Length and set the Initial Conditions to a Pressure of 1.05 [bar]. the Y-junction Panel for the collector should appear as in Figure 4. click on the auto-calculate buttons to fill in the Volume and Heat Transfer/Skin Friction Area fields automatically. Once the Diameter of 80 [mm] has been entered. out of the plane of the runners. as shown in Figure 5. Orient the massless duct leaving the collector to be facing down.Figure 4: Collector Y-Junction Panel Orient the ducts as they are displayed in the schematic in Figure 1. . the model should appear as in Figure 6.Figure 5: Collector Duct Orientation When completed. . The Catalytic Converter The catalytic converter consists of entry and exit cones that will be modeled using volumes and a brick. to represent the geometry of the brick.Figure 6: Model with Completed Manifold Save your model Select the Save As. The catalyst duct allows the user to input typical catalyst measures. ... option from the File pull-down menu and give the model a new name. like cell density. Proceed to Step 2 . which can be modeled using a catalyst duct. Saving this file and running it with a different name will allow comparison of results to the models built and analyzed earlier.Adding the Exhaust System and Creating Spatial Plots in WavePost Step 2 .wvm.The Catalytic Converter Show SI Tutorial. Phase 5 . such as tut_si4_exhaust. 0\examples\engine\TUT_si\tut_si4_exhaust. Drag and drop the required elements onto the canvas and connect them.wps 2.wvm Example Output File: .1 The Basic Geometry 2. Don't forget to attach the dangling end of the massless duct created with the exhaust manifold to the Y-junction representing the entry cone. In WaveBuild.Chapter sections 2. the entry and exit cones can be modeled using Complex Y-junctions and the catalyst brick can be modeled using a single Catalyst Duct connecting the two junctions.\Ricardo\WAVE\8.\Ricardo\WAVE\8.3 The Brick as a Catalyst Duct Example Input File: .1 The Basic Geometry The schematic of the catalytic converter is shown in Figure 1.0\examples\engine\TUT_si\tut_si4_exhaust. See Figure 2.2 The Entry and Exit Cones 2. Figure 1: Catalytic Convert Schematic . 1100 [K] Temperature.Figure 2: Required Junctions and Duct 2. and 900 [K] Wall Temperature (see Figure 3). the Volumes and Heat Transfer/Skin Friction Areas are taken from solid-modeling software (CAD).2 The Entry and Exit Cones The entry and exit cones of the catalytic converter are modeled using complex Y-junctions in order to account for the pressure loss due to sudden expansion of the gas.05 [bar] Pressure. so using a duct to model the entry/exit cones won't capture the pressure loss due to sudden expansion (see sidebar on Modeling Tapered Ducts). The Diameters provided are the area-weighted average diameters. . The taper angle in these cones typically far exceeds the recommended maximum of 7. Set the Initial Conditions to be 1. Double-click on the entry and exit cone Y-junctions and edit their settings to reflect the information given in the schematic. identical to the junction diameter setting: 90.4 [mm] for the exit cone. Coeff. Set a Disch. The DELX values for both connections should be the length of the cone (50 [mm] for both junctions) while the DIAB value can be left as the default value for now.95 for both the entrance and exit connections of the catalyst to account for the tapered cone geometry (see Figure 4).2 [mm] for the entry cone and 76.Figure 3: Entry Cone Y-Junction Panel Orient the duct connections to be directly across from each other for each Y-junction. of 0. . Given the geometry of the brick. . a Cell Wall Thickness of 4 [mil]. the catalyst duct should be specified to have a Cross Sectional Area of 7854 [mm2].Figure 4: Catalyst Duct Orientation 2. The Catalyst Duct is simply an element which allows input of basic geometric parameters of a the brick in order to describe the single flow channel.3 The Brick as a Catalyst Duct The catalyst brick itself is modeled using a single Catalyst Duct which will actually only represent one channel through the brick but creates a number of identical channels to represent the entire brick. a Perimeter of 314. Figure 5 shows the method used to calculate the diameter of a single catalyst brick channel and the number of identical channels.59 [mm]. and a Cell Density of 600 [1/in2]. It assumes that all channels are square in shape. .Figure 5: Calculating Catalyst Geometry The Overall Length should be 80 [mm] as shown in Figure 1 and remember to set the Discretization Length to 40 [mm].055 [mm]. as shown in Figure 6. the Cell Count should be equal to 7304 and the Cell Diameter(single channel) should be 1. Using the formula shown in Figure 5. A common practice when modeling Catalytic Converters in steady-state. set the Pressure to 1. such as 5.05 [bar]. is to set the brick Wall Temperature to match the temperature of the gas on the downstream side of the catalyst (from the test data) and then set the Heat Transfer Multiplier to a high value. click Yes and enter the values as shown in Figure 7.17 [mm] (this represents the expansion diameter for a single channel entering the volume). When prompted to add CAT_TEMP to the Constants Table. and the Wall Temperature to a constant named {CAT_TEMP}. . On the Initial Conditions tab. if test data is available. Edit the duct settings and click on the Coefficients tab to set the Heat Transfer value to 5.Figure 6: Catalyst Brick Geometry Edit the neighboring Y-junctions representing the entry and exit cones and set the DIAB value for the catalyst duct connection to be 1. the Fluid Temperature to 1100 [K]. This ensures that the gas temperature leaving the brick matches the calibration data. Figure 7: Catalyst Brick Wall Temperatures When completed. the model should appear as in Figure 8. Proceed to 3. Figure 8: Model with Catalytic Converter Save your model Click on the Save button in the toolbar to save the file. The Resonator (Silencer) . Show SI Tutorial.1 The Basic Geometry The schematic of the down pipe (from the catalytic converter) and resonator is shown in Figure 1.Adding the Exhaust System and Creating Spatial Plots in WavePost Step 3 . concentric tube (can) around it.0\examples\engine\TUT_si\tut_si4_exhaust. perforated duct and the surrounding can. .\Ricardo\WAVE\8. the down pipe can be modeled as two curved ducts and the resonator can be modeled as entry and exit ducts with Complex Y-junctions representing the entire length of the inner.2 The Down Pipe 3.wvm Example Output File: .\Ricardo\WAVE\8.wps 3. Chapter sections 3. The resonator is modeled in WaveBuild as a series of complex y-junctions connected by massless ducts. The resonator acts as a muffler and dampens certain frequencies in the exhaust stream.The Resonator (Silencer) The resonator is simply a perforated tube with a larger. In WaveBuild. Phase 5 .1 The Basic Geometry 3.3 The Resonator Example Input File: .0\examples\engine\TUT_si\tut_si4_exhaust. Draw the ducts representing the down pipe starting from the exit cone of the catalytic converter. to represent the ends of the ducts used to model the downpipe.2 The Down Pipe Drag and drop two orifice elements onto the canvas as shown in Figure 2. .Figure 1: Down pipe and resonator schematic 3. use control points to represent the bend angle on the canvas. . If desired. Include a 90° Bend Angle for each duct and remember to use a Discretization Length of 40 [mm]. Set the Initial Conditions to 1. the canvas should appear similar to Figure 3.Figure 2: Down pipe junctions Enter the geometric properties as shown in the schematic in Figure 1.05 [bar] Pressure and1000 [K] Fluid Temperature with 800 [K] Wall Temperature. With the down pipe modeled. . Complex Yjunctions representing the inner perforated duct and the surrounding can.Figure 3: Down pipe ducts 3. and a short exit duct. The completed WaveBuild representation of the resonator appears in Figure 4.3 The Resonator The resonator is modeled with a short entry duct (40 mm long as shown in Figure 1). Figure 4: Resonator representation The number of consecutive Complex Y-junctions to use can be determined by dividing the total length of the can (300 mm) by the exhaust discretization size (40 mm). the total Heat Transfer/Skin Friction Area for the single Y-junction is 3866. The Y-junction panel and pipe orientations should appear as in Figures 5 and 6.89 mm 2. The results in 7 Complex Yjunctions used in series to represent the inner perforated duct and 7 more used to represent the surrounding can.8 [mm3] The Heat Transfer/Skin Friction Area can be calculated from the area of the pipe minus the area of the perforates connecting to the outer can. 900 [K] Fluid Temperature.857 mm long (300mm/7) and 50 mm in Diameter. The first Y-junction representing the inner perforated duct is cylindrical -. we can calculate the surface area of a single Y-junction as 1/7th of the total surface area. Thus. The area of the perforated section of pipe is 47123. The easiest method for building this resonator model is to build and define the first Complex Y-junction for the inner duct and outer can each. The total area of the perforates account for 20057. and then copy/paste them 6 times. This means it has a Volume of 84149. Set the Initial Conditions to 1. and 700 [K] Wall Temperature.05 [bar] Pressure.5 mm 2.63 [mm2].42. Assuming the perforates are evenly distributed along the entire length of the pipe. . perforated pipe y-junction .Figure 5: Inner. and 600 [K] Wall Temperature.4 [mm3] The Heat Transfer/Skin Friction Area of the entire outer can. or doughnut-shaped volume. The resulting Volume is 393686. 800 [K] Fluid Temperature.Figure 6: Inner. This creates a torus. with the volume representing the inner duct subtracted (don't forget to include the 1 mm thickness of the tube wall). perforated pipe y-junction orientation The first Y-junction representing the outer can is cylindrical as well.05 [bar] Pressure. including the end-caps can be averaged over all seven Y-junctions.3 [mm2]. Set the Initial Conditions to 1. . The Y-junction panel and pipe orientations should appear as in Figure 7 and 8. and is 18781.15 [mm]. with an equivalent Diameter of 108. Figure 7: Outer can y-junction . And each inner. perforated pipe Y-junction should be connected to the adjacent outer can Y-junction by amassless duct which represents the perforates. assuming they are evenly distributed). with a Diameter of 11.3 [mm] and a Count of 28. All of the Y-Junctions representing the inner.15 [mm]. .57 (=200/7.Figure 8: Outer can y-junction orientation Copy/paste the two Y-junctions to create seven of each. perforated pipe should be connected by massless ducts with Diameters of 50 [mm]. All of the Y-junctions representing the outer can should be connected by massless ducts with Diameters of 108. in series as shown in the figure below. The complex muffler will be modeled as a series of inter- .1 The Basic . Phase 5 .0\examples\engine\TUT_si\tut_si4_exhaust. Due to the complexity and tediousness of modeling this muffler. please contact your Ricardo Software Sales representative at (734) 394-3860 or via email at RS_Sales@ricardo. the two segments that represent the mid-pipe can be modeled simply as two ducts. Chapter Example Input File: sections 4.com. Ricardo Software has developed such a tool – named WaveBuild3D.The Complex Muffler (Optional) The complex muffler is a complicated portion of any WAVE model. It usually consists of multiple pipes.wvm Geometry 4. Fortunately.3 Modeling the Muffler in Quasi2D .2 The Mid-Pipe Example Output File: 4. it is NOT mandatory for you to build it. but it is recommended that you understand the idea behind it and appreciate the need for a routine engineering tool to automatically mesh and generate a WAVE input file for such complex components. In WaveBuild. WaveBuild3D is especially useful for auto-meshing intake and exhaust components for NVH applications. It may have packing material made of rock wool or fiberglass in portions of the volume. starting from the orifice junction at the end of the resonator. possibly perforated.Adding the Exhaust System and Creating Spatial Plots in WavePost Step 4 . Proceed to Step 4 .Figure 9: Connectivity using massless ducts Save your model Click on the Save button in the toolbar to save the file. passing through internal baffles within a large complex-shaped volume.\Ricardo\WAVE\8. For more information about this tool. used to dampen acoustic transmissions.wps 4.\Ricardo\WAVE\8.The Complex Muffler Show SI Tutorial.0\examples\engine\TUT_si\tut_si4_exhaust.1 The Basic Geometry The schematic of the mid-pipe and complex muffler is shown in Figure 1. Figure 1: Mid-Pipe and Complex Muffler Schematic 4. . Draw the ducts representing the mid-pipe starting from the orifice junction at the exit of the resonator. to represent the ends of the ducts used to model the mid-pipe. massless duct connections.connected Complex Y-junctions.2 The Mid-Pipe Drag and drop two orifice elements onto the canvas as shown in Figure 2. and normal ducts for the muffler entrance and tailpipe. The level of refinement is up to the user and what kind of results they desire: for performance. Quasi-2D meshing (Box A in Figure 4) is sub-division of volumes in 2 axial directions (X and Y. If desired. in this case) and ignoring the division in the 3rd direction (Z axis). Figure 3: Mid-Pipe Ducts 4. should be sub-divided and modeled with multiple Complex Y-junctions. Each section of perforated pipe will also have to be represented by Complex Y-junctions attached to the surrounding volume(s) with multi-count massless ducts to represent the perforates. Include a 90° Bend Angle for the first duct and remember to use a Discretization Length of 40 [mm]. The number of subvolumes increases dramatically between Quasi-2D and Quasi-3D meshing! . use control points to represent the bend angle on the canvas.3 Modeling the Muffler in Quasi-2D Because the muffler is such a large and complex volume. detailed Quasi-3D meshing should be performed. as in the resonator. simple Quasi-2D meshing may be sufficient but for acoustics. as shown in the schematic. Set the Initial Conditions to 1. Quasi-3D meshing (Box B in Figure 4) is sub-dividing volumes in all 3 axial directions. With the mid-pipe modeled.Figure 2: Mid-Pipe Junctions Enter the geometric properties as shown in the schematic in Figure 1. the canvas should appear similar to Figure 3.05 [bar] Pressure and800 [K] Fluid Temperature with 600 [K] Wall Temperature. the three internal chambers which physically divide the muffler vertically. We refer to meshing in WAVE as "Quasi" meshing as it is not identical to full-scale 3-D CFD but can approximate the same results. Ricardo Software introduced WaveBuild3D as an auto-mesher for large components in the intake and exhaust systems using a solid-modeling interface to represent the geometry. * Based on average time an engineer spends to complete one complex Y-junction input = 6 minutes ** Based on meshing using Intel Core 2 Duo T7600 # of Subvolumes (Matrix Size) Meshing Type 2D/3D # of Repeated Tasks Engineer Minutes* WaveBuild3D Minutes** 3x3 2D 18 108 0.37 15 x 15 x 15 3D 6750 40500 0. For this reason. and Complex Y-junctions. At this point there is nothing new to learn. the new WAVE user. it's only routine work that could to be automated! It is expensive and tedious for you. Also. pre-processing time of manual meshing (by you the user) and WaveBuild3D (computer program auto-meshing).83 nxnxn 3D 2 x n3 2 x n3 x 6 – It is left to you. massless ducts. massless ducts. the engineer.Figure 4: Modeling in Multiple Dimensions The complexity of this connectivity of Y-junctions. The table below shows a comparison for different mesh matrix sizes vs.05 9x9x9 3D 1458 8748 0.03 3x3x3 3D 54 324 0. All that needs to be done is repeating the geometric and duct orientation input many times to model the muffler as a network of ducts. this modeling work has no real engineering value. to spend your time on such laborious tasks. to complete modeling the muffler. and normal ducts has no uniquelycorrect design and different designers might end up with different connectivity matrices for this same muffler. The muffler is shown in WaveBuild3D in Figure 5 and the corresponding WAVE mesh is shown in Figure 6. . This muffler component is shipped as an example model. Drag and drop the SI_Muffler component onto the canvas and connect it to the model by attaching the last duct of the mid pipe (the last orifice element can be deleted. the model should appear similar to Figure 7. To add it to the model. regardless of whether or not the user has a WaveBuild3D license. Any WaveBuild3D component can be used in any WAVE model. as it is no longer necessary) to the inlet connection point of the component. Connect the outlet connection point of the muffler component to the Exhaust ambient using a duct with 50 [mm] diameters and an overall length of 40 [mm] (use initial conditions similar to the mid-pipe). expand the Tags branch under the Components branch of the Elements tree. .Figure 5: Muffler in WaveBuild3D Figure 6: Muffler mesh from WaveBuild3D The WaveBuild3D tool creates portions of WAVE models known as Components. When finished. mpg files for use in presentations and reports.Figure 7: Completed Model in WaveBuild Save your model Click on the Save button in the toolbar to save the file.wvm 5.Creating Spatial Plots in WavePost WavePost can use time-based data to create plots of scalar/vector quantities along a length of the network to observe traveling pressure waves. etc. Phase 5 .\Ricardo\WAVE\8.1 Creating .Adding the Exhaust System and Creating Spatial Plots in WavePost Step 5 .0\examples\engine\TUT_si\tut_si4_intake. Chapter sections Example Input File: .Creating Spatial Plots in WavePost Show SI Tutorial. Proceed to Step 5 . temperature profiles. These spatial plots can be animated to observe the temporal change in WavePost and saved as . click the Open File button in the toolbar and open the . A Query window will pop-up prompting whether to add curves to the existing plots using this file.wvm currently loaded in WaveBuild.wvd file for the WAVE model containing both the intake and exhaust systems (tut_si4_exhaust).Spatial Plots in WavePost 5. Launch WavePost from WaveBuild by clicking in the Launch WavePost button in the WaveBuild toolbar . It should contain sweep plots created during the in Phase 3 of torque. click the OK button to save and run sequentially).wvd and .2 Animating Spatial Plots Example Output File: . On the Canvas of the WavePost GUI. This WavePost session file is currently referencing results from the 4-cylinder model without intake/exhaust (tut_si4) and from the four-cylinder model with intake only (tut_si4_intake).wvd and . Once WavePost is open. use the Shift+Left Click to multiple-select the ducts and junctions along the intake runner to the cyl1 junction (see Figure 1). .wps. as shown in Figure 2. This will open the.wps 5. Click on the Add button at the bottom of the Output Files frame and select the newly created .sum files for this WAVE run will be added to the Output Files list.1 Creating Spatial Plots in WavePost Run the WAVE model by clicking on the Run Screen Mode button in the toolbar (if prompted to save the model before running WAVE.wps file created in Phase 3. Click on the Yes button and every existing plot will add data from the newly added. Open the Sweep Plots to view the comparison of the performance parameters. Comparison.0\examples\engine\TUT_si\tut_si4_intake. etc.\Ricardo\WAVE\8. power.sum files (if matching data exists in the new files). Right-click on one of the ducts/junctions in the highlighted group and select the "Add Spatial Plot > Basic > Pressure" menu item.wps file named similarly to . The . Figure 1: Ducts and Junctions for Spatial Plot . showing a scaled view of the ducts/junctions along the path and the pressure profile in those ducts/junctions on the same plot (see Figure 3).Figure 2: Adding a spatial plot via the context menu A Spatial Plot of the pressure along this path will be automatically created. Figure 3: Spatial Plot Display Panel . Therepresentation of the ducts/junctions can be moved using the middle mouse button or removed from the plot altogether by double-clicking on it and de-selecting the Display Scale View option. where the crank animation can also be displayed (also accessible from the Tools > Display pull-down menu item). The Time Offset can be set to change the starting point of the animation. as demonstrated in Phase 4.Figure 4: Spatial Plot of Pressure in Runner 1 5. menu option from the Tools pull-down menu (seeFigure 5). The animation can be played or recorded to a MPEG file for use in reports/presentations. Figure 5: Spatial Plot Animation Panel The Animated Spatial Plot should appear as the video at the bottom of the page... allowing multiple spatial plots to be shown in/out of phase.2 Animating Spatial Plots Spatial Plots can be animated just like canvas displays of network variables. Simply open the Animation Panel by selecting the Animation. . wps file.Save your file Click on the Save button in the toolbar to save the updated Comparison. Optional phases follow to elaborate on the basic principles. . CONGRATULATIONS! The 4-cylinder model is complete! All of the basic principles in WAVE modeling have been introduced and explained as well as the basic methods of building a model and post-processing the data.