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• In the Post-process panel, select Engine from the drop-down menu
• Click the ellipsis (...) button and select es-ice.pos from the file browser
• Click Add to add es-ice.pos to the Data files box
• Click Read data
• Select the Net indicated work,
Power and IMEP toggle buttons to calculate these quantities
• Select the Cycle toggle button to calculate results over a full 720 degree CA engine cycle
• Set the Start angle to 360
• Click Calculate
The results are displayed in the main es-ice panel, as shown below.
Creating a Velocity Vector Display
This section describes the creation of a velocity vector display at the maximum intake valve opening, on a plane crossing the valve centreline. The image is created using pro-STAR post-processing facilities, which require access to the model file (.mdl), events file (.evn), geometry file (.ccmg) and transient data file (.ccmt) saved for this case.
First, load the required time step and store the corresponding velocity data.
•In the pro-STAR Model Guide, select the Post Processing > Load Data panel, shown to the left of Figure 9-7
•Select Transient from the Analysis drop-down menu
•Select Yes from the Moving Mesh drop-down menu
•Click Add File
•In the Transient box, select star.ccmt
•Click Open Transient File
•In the Time Step box, select time step 30. This time step is the point in the simulation when the intake valve is fully open.
•Click Store Time
•Select the Data tab (shown to the right of Figure 9-7)
•In the Vector Data box, select Velocity Components UVW
•Click Get Data
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Figure 9-7 Tabs Files and Data in the Post Processing > Load Data panel
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Having loaded the relevant data, proceed with the plot creation.
•In the Post Processing > Create Plots panel, select the Section/Clipped tab
•In the Single Plane Plot box, set the Point coordinates to 0, 19.5, 0 and the Normal coordinates to 0, 1, 0. These define a plane that crosses the valve centreline and has a normal in the positive y-direction.
•Click Apply
• Click Plot to Screen
Manipulate the view using the mouse or appropriate commands to display the results, as shown in Figure 9-8.
Figure 9-8 Section plot of velocity vectors at maximum intake valve opening
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Creating an Animation of Fuel Concentration |
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Creating an Animation of Fuel Concentration
This section provides an example of how a pro-STAR input file (scalar1.inp) can be used to create an animation of fuel concentration throughout the transient simulation. Opening the input file with a text editor will display its contents as shown below. For clarity, the full command names are shown although the usual four-letter abbreviations can be used instead.
•Connect the events file to the pro-STAR session and load the transient data
RESUME, , EVFILE, CONNECT TRLOAD, ,
•Create a custom colour table for use with the colour scale
CLRTABLE, POST, 1, 1.00, 0.00, 0.00, 1.0 CLRTABLE, POST, 2, 1.00, 0.20, 0.00, 1.0 CLRTABLE, POST, 3, 1.00, 0.40, 0.00, 1.0 CLRTABLE, POST, 4, 1.00, 0.55, 0.00, 1.0 CLRTABLE, POST, 5, 1.00, 0.70, 0.00, 1.0 CLRTABLE, POST, 6, 1.00, 0.80, 0.00, 1.0 CLRTABLE, POST, 7, 1.00, 0.90, 0.00, 1.0 CLRTABLE, POST, 8, 1.00, 1.00, 0.00, 1.0 CLRTABLE, POST, 9, 0.85, 1.00, 0.10, 1.0 CLRTABLE, POST, 10, 0.70, 1.00, 0.25, 1.0 CLRTABLE, POST, 11, 0.55, 1.00, 0.40, 1.0 CLRTABLE, POST, 12, 0.40, 1.00, 0.55, 1.0 CLRTABLE, POST, 13, 0.25, 1.00, 0.70, 1.0 CLRTABLE, POST, 14, 0.10, 1.00, 0.85, 1.0 CLRTABLE, POST, 15, 0.00, 1.00, 1.00, 1.0 CLRTABLE, POST, 16, 0.00, 0.90, 1.00, 1.0 CLRTABLE, POST, 17, 0.00, 0.80, 1.00, 1.0 CLRTABLE, POST, 18, 0.00, 0.70, 1.00, 1.0 CLRTABLE, POST, 19, 0.00, 0.55, 1.00, 1.0 CLRTABLE, POST, 20, 0.00, 0.40, 1.00, 1.0
•Specify a 20-colour scale with a user-defined value range of 0 to 0.76E-01
CSCALE, 20, USER, 0, 0.76E-01
•Set up the display items
PLLOCALCOOR, OFF, ALL PLDISPLAY, OFF, ALL PLDISPLAY, ON, LOGO PLDISPLAY, ON, HEAD PLDISPLAY, ON, MINMAX PLDISPLAY, ON, SCALE, ,8 PLMESH, OFF
•Set up the viewing position
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VIEW, -1, -1, 0.5
CENTER, -5, 5, -20
DISTANCE, 75
•Select the Extended Graphics display option and a 1024 x 768 resolution for the image
TERMINAL, , EXTENDED HRSDUMP, IMAGE, 1024, 768
•Specify the basic plotting option
POPTION, CONTOUR
•Set up a variable, it, that will be incremented at each loop iteration and begin the loop definition
*SET, it, 1, 1 *DEFINE, NOEXECUTE
•Store the next time step
STORE, NEXT
•Set up a crank-angle display label in the lower-right corner of the screen
*GET, TIME, time
*SET, CRANK, 3600 * TIME * 6 + 320 TSCALE, 4, 15
PLLABEL, 1, FORMAT, , 4, 10, 0.5 CRANK
F6.1, ' degCA'
•Plot cell-averaged fuel scalar data
GETCELL, CONC, 1 CSET, ALL CAVERAGE, CSET CPLOT
•Create a counter for the filenames
*SET, itn, 1000 + it *SCOPY, itn, sitn, i4
•Store the current display to a .gif file
*SSET, sname, image_1_{sitn} HRSDUMP, GIF, {sname}
•End the loop definition and then execute the loop for all time steps
*END
*LOOP, 0, 152
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Note that useful information on how to create post-processing input files can be found in the STAR-CD documentation set, volumes “pro-STAR Commands” and “Post-Processing User Guide”.
Input files can be used for running pro-STAR in batch mode to generate images and animations without accessing the GUI. This facility produces consistent output for several different models and simplifies the comparison of results.
Off-screen rendering with pro-STAR is not currently supported for Windows. This means that the ability to use pro-STAR in batch mode to generate images and animations is not available in the Windows environment. However, you can still use the input file described above within the pro-STAR GUI by entering the following command:
IFILE, scalar1.inp
Note that when accessing an input file in the pro-STAR GUI, you need to add a c after the TRLOAD, , command as the software will prompt you to continue listing the available time steps. This addition is not required when pro-STAR is running in batch mode as the software will not prompt for input.
The following is an example of a batch script for a Linux machine to create a fuel distribution animation. The script employs third-party software (Gifsicle) to create animations using several .gif files.
•Run pro-STAR in batch mode, with input redirection to answer prompts, and load the star.mdl model file
prostar gl -b << EOF star
y y
•Read the input file and execute its commands
IFILE, scalar1.inp
•Quit pro-STAR without saving and complete the input redirection
QUIT, NOSAVE EOF
•Create an animation file called scalar1.gif using Gifsicle
gifsicle -d 10 -l -o scalar1.gif image*.gif
Figure 9-9 shows the fuel distribution in the cylinder at 400 degrees CA.
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