【摘要】 对一1.25L单缸4气门发动机进行可变进气的改进设计,以便优化发动机的中小负荷性能。以初步设计的进气道模型为基础,建立了评价进气道稳流特性的计算模型,对不同进气模式在不同的气门升程下的进气道和缸内流场进行了模拟计算,得出了进气道内的气流分布、流量系数、涡流比和滚流比等参数,并与气道稳流试验数据进行了对比分析。更多还原

【Abstract】 An improving design on the variable intake port of a 1.25L 4 valve single cylinder engine is conducted for optimizing the small and medium load performance of the engine.A computing model for evaluating the steady flow characteristics of intake port is set up based on the intake port model preliminarily designed.And the simulation computations on the intake port and in-cylinder flow fields in different valve lifts under different intake modes are performed and the parameters such as air flow distribution,flow coefficient,swirl ratio and tumble ratio of intake port are obtained,which are compared with test data of the steady flow of intake port.更多还原