Abstract
Keywords: 3D modelling, CFD, fluid flow, turbulence
In this paper some initial results concerning the evolution of the 3D fluid flow pattern in combustion chamber imposed by fluid ingress through port/valve assembly were presented. Three different types of combustion chanbers are considered all with flat cylinder head and vertical valves. Intake and exhaust ports are rounded and canted with identical elevation angle. The results were obtained by dint of multidimensional numerical modeling of nonreactive flow in arbitrary geometry with moving objects and boundaries. The fluid flow pattern during induction and compression is extremely complicated and entirely three-dimensional. It should be noted that all three types of organized macro flows are encountered i.e tumble, squish and swirl yielding fairly convenient conditions for combustion thereafter. The swirl motion was not encountered in first two cases (flat piston head and cylindrical bowl) under all other unaltered conditions.