Effect of Radial Leakage on Combustion Characteristics in Rotary Engines: Experimental and Numerical Investigation

To further investigate the influence of the law of leakage on rotary engines, this study took a single-cylinder gasoline rotary engine as the research object and analyzed the effects of radial leakage, using the experimentally validated 3D combustion simulation model as the basis, and equivalent leakage area on in-cylinder flow, combustion process, and engine performance. The study shows the following: on the one hand, leakage disperses the force exerted by the rotor on the in-cylinder fluid and flame, thereby changing the fluid direction; on the other hand, it increases the distribution area of high-speed fluid in the middle and rear parts of the combustion chamber and reduces the overall flow velocity in the front part. Radial leakage has the characteristics of both a slight positive promotion and a negative interference on combustion, and the increase in equivalent leakage area will strengthen the negative effect. Meanwhile, it reduces the combustion efficiency, causes a significant decrease in cylinder pressure and maximum cylinder temperature, and exerts an adverse impact on the overall performance of the engine.