A study of flow phenomena in internal (piston) combustion engines

A zero dimensional model of the intake stroke, and a three dimensional model of the inlet port flow (for the cylinder head swirl coefficient) of an internal combustion engine were developed. Electric discharge anemometers were designed in order to check model predictions. Tests on a motorcycle engine show that solid body approximation, used in the zero dimension model, is practicable, although the intake flow still has a clear effect during the compression stroke. The calculated initial swirl rev is much lower than measured. Measurements in a direct injection diesel engine were compared with initial conditions of the 3-D simulation. The calculated initial swirl rev is higher than measured. The calculated and measured results of the swirl coefficient agree.