Flow Visualisation of Process of Producing Induction Swirl using a Water Model

Abstract

This paper is concerned with an experimental investigation on the process of producing an induction swirl in a four cycle engine. A water model test based on dynamic similarity was executed using three kinds of intake valves connected with a directed port. In-cylinder flows during the intake stroke in the model were visualized by tracer particles. Two kinds of methods were adopted in their analysis . One is a technique using a movie camera and the other is simultaneous photography using a pair of still cameras. The main feature of the induction swirl was clarified by analysis of the traces. The results show that the intake valve geometry makes a difference in the induction swirl and the local swirl intensity of the cylinder.