William Kuran

Flow Simulation of Air Compressing in a Cylinder

Discussion created by William Kuran on Dec 23, 2020
Latest reply on Jan 5, 2021 by William Kuran

I am trying to model air as it compresses (compression stroke) in a sidevalve engine.  The area of most interest is the last 15 degrees of crankshaft rotation before the piston reaches top dead center (TDC).  That 15 degrees of crankshaft rotation translates to 0.110 inch of  piston linear motion.  At the engine rpm of interest (5142), the piston travels that 0.110 inch in 0.486 ms.  At TDC the piston to cylinder head clearance is 0.040 inch.  The compression ratio is 8.5:1. Piston stroke is 4.8 inches.

I would like to see what is referred to as squish (air movement as the piston approaches TDC.

The attached image represents the geometry.


I've only done one CFD analysis that modeled coolant flow through the cylinder head.  Setting up the study was fairly intuitive.  With this model, I have not been able to get started.


Would you consider pointing me in the right direction to get started.  A stretch goal is to then model flow through the valves.