Gas Flow Simulation and Visualization in Cylinder of Motor-Cycle Engine

In gasoline engines for motorcycles, there are various restrictions on the intake duct shape imposed by the limitations of the engine mounting space and layout. The intake duct shape (intake port and manifold shape) has a great influence on the in-cylinder flow (swirl and tumble flow). Therefore, the fundamental technologies of flow visualization experiments and numerical simulation are needed for the design of high-performance engines. In this paper, we present good agreement of results by visualization experiments and numerical simulations of in-cylinder flow for such factors as flow pattern and swirl ratio.