Learning Forum

[h.al-wakeel]

HI,

I am simulating an internal combustion engine using Ansys-Forte. The geometry is taken from Tutorial- Chapter 5: port-injected spark ignition engine.

How can the volume at TDC be changed to correct the compression ratio, please?

Thanks

[jcooper]

Hi Haitham:

There are a number of different ways to affect the compression ratio of an engine geometry without changing the CAD geometry, depending on what really happens in the engine hardware:

1) Adjust the stroke value on the piston boundary condition panel;

2) Adjust the squish height by moving the piston in the imported surface mesh;

3) If the engine contains a volume representing the crevice region, adjust the height of the crevice region. The "Compression Ratio Calculator" described in section 2.8.15 of Forte User's Guide can be used to check the CR value during the setup stage.

 

Best Regards,

Judy