航空活塞二冲程发动机的可变排气阀换气过程

The ventilation process of the aviation piston two-stroke engine directly affects the engine performance, and the variable exhaust valve can improve the dynamic performance of engine. Through the GT-Power to build the one-dimensional engine model, simulation research about ventilation process of the engine at different speeds and different exhaust valve stages was carried out, and the influence of exhaust valve stage on the ventilation process was analyzed. On this basis, the stage of the exhaust valve under constant speed cruise conditions (speed of 6500r/min, 50% throttle opening) was also optimized. The results show that different exhaust valve stage can change the phase of pressure fluctuations during engine exhaust process, thereby affecting the engine's ventilation quality and combustion process; under constant speed cruise conditions, when the exhaust valve is at medium stage (primary valve is closed, secondary valve is open), engine power performance is the best.