a cycle (engine) simulation model

The aim of this assignment is to understand and utilise a cycle (engine) simulation model made using Microsoft Excel

1. For an engine of your choice (this may be based on your own car or bike, or any vehicle that you can get the information for) you are required to input the

correct geometry and initial conditions into the simulation (blue boxes). You should change these values until they match the engine you are interested in.

2. You should set the initial conditions (green boxes) to reasonable values, explaining your choices. You should also explain the effects that increasing or

decreasing these values have on the model.

3. You now need to select suitable values for the polytropic index for compression and expansion (pink boxes) explaining your choices with reference to adiabatic,

isothermal and polytropic processes and the differences between them.

4. Explain why the values Gamma and Rare used in the model, what they are, and to what degree do they change the results of the model. Try to find a suitable

value for Gamma.

5. Using the RPM box (purple) you are able to control the ‘speed’ of the cycle. You should create a graph of RPM against POWER for the engine you have chosen,

explaining what values of n you are using at each different speed (only 5 different speeds are needed). Why do the different speeds need different values of n?

6. The model is based on the Otto cycle. Explain the differences between the PV diagram created by the model and the PV diagram from an ideal Otto cycle. What