Numerical Simulation of Gas Flows in the Cylinders of Four-stroke Cycle Ergines : 1st Report, Analysis of the Process of Swirl Generation during Intake Stroke

Abstract

A method for calculating the three-dimensional gas flows during intake stroke in the cylinders of four-stroke cycle engines has been examined using simplified model engines. The process of induction swirl generation in a model engine with an off-center intake valve has been simulated numerically. The results show that the flow pattern in the cylinder varies in many ways with the distribution of inflow velocities around the intake valve. The effects of the differences in inflow velocity distribution (helical-port and directional-port type) on the generation of swirl are predicted.