GT-POWER Assignment#1

MEEM 4220 - I.C. Engines

GT-POWER Assignment #1

Objectives:

1. Run a fully developed 4-cylinder engine model in GT-Power. Produce a plot of cylinder pressure versus crank position/angle (similar to Figure 1.8 in Heywood textbook). Please do a combined plot for engine speeds of 2000 RPM and 5000 RPM.

2. Determine the crank angle degree at which the exhaust valve opens and the crank angle degree at which the exhaust valve closes.

3. Turn in a brief report that includes:

(a) a general but brief explanation of what you did,

(b) a graph of pressure vs. crank angle,

(c) comments on the similarities/differences for the two speeds considered,

(d) comments on the differences between your results and Fig. 1.8,

(e) values of EVO and EVC timing, and an explanation of where you found them.

Procedure:

1. The 4-cylinder engine model required for Assignment#1(“master-model.gtm”) can be found at www.me.mtu.edu/~smathur. Save the model as “4cyl-assignment1.gtm” in your home directory.

2. Open GT-ISE: On PC go to Start→ Programs→ GTI Applications Group→ GTise v6.1.0. Open the 4-cylinder model mentioned above using File/Open.

3. Enter “Case Setup” from the “Run” menu in GT-Power. Case 1 with RPM value of 2000 is already in the model. We need to create another case with RPM value of 5000. To accomplish this, click on “Append Case”. Then in Case 2, change the value of RPM to 5000. Also go to the parameter “CASE” and in the description of Case 1 and Case 2 type “2000rpm” and “5000rpm” respectively. Click OK.

4. Run the Simulation Preprocessor (Blue icon)

5. If no errors, run the Simulation (Yellow icon)

6. Once the model has run successfully, the results can be viewed with GT-POST. From the Run men select “Open GT-POST”.

7. To view all the available plots, go to menu “View” and select “View All Checked”. (Alternately this can be done by clicking on the icon that shows two lines intersecting). The plot we are interested in is on page 3 (use the plot navigation arrows towards the end of the icon bar to view all the pages). To view only the plots related to engine cylinder, you can right click on “EngCylinder:Cylinder01” in the .gx File Pane and select view. Also use the Case selector just above the .gx File Pane to view other cases.

8. In order to obtain a combined plot of cylinder pressure versus crank position/angle for 2000 RPM and 5000 RPM, we will use “Plot Case Combine”. Go to “Plot Case Combine” (the icon which shows a bunch of lines in a plot.). Expand the “EngCylinder:Cylinder01” option and then expand the pressure. Click on Cylinder01. Notice that two cases appear on the right side of the screen. Select them both and click OK. The desired plot should appear on the screen.

9. Find the crank angles at which the exhaust value opens and closes: Explore the object definitions and the input parameters in Case Setup. Remember the Help menu is usually accessible from the object definition menu by clicking the icon in the upper left corner.

DUE DATE: Wednesday, Sept. 14, beginning of class.