| 摘要 |
PURPOSE:To improve the entire performance of an engine by either making the surface roughness of a part of the inner surface of a port rougher or providing a group of small projections and varying a swirl ratio with respect to an engine speed. CONSTITUTION:A turbulence 08 occurs in the flow of air near the wall surface part inside a suction port 03, due to a rougher surface of surface roughness or a group of small projections 031 provided on the surface part of the suction port 03. The degree of turbulence becomes greater with increase in velocity, the difference from a smooth part is increased, the velocity distribution is varied, causing change in velocity distribution of air which flows into a cylinder from around a suction valve 01. The figure 061 indicates the flow of feed air, which flows into a cylinder from around the suction valve 01 through the valve 01, 05 indicates an exhaust valve, and 07 indicates a fuel valve (in the case of Diesel engine) or an ignition plug (in the case of gasoline engine). |
