柴油机气道进气流动特性及进气门杆形状对其影响分析
Research on inlet flow characteristics in diesel engine and the impact of the shape of the intake valve stem on the inlet flow characteristics

建立某RD190柴油机螺旋进气道稳态CFD模拟计算模型，对其流动特性进行研究，分析得到了气道流量系数和涡流比、柴油机的外特性结果，并采用CFD模拟分析了进气门杆形状对进气流动的影响. 研究结果表明：随着截面比的增加，平均流量系数和平均涡流比均为先增大后减小，当截面比在0.28～0.30时，进气道平均流量系数相对原方案值变化不大，而平均涡流比最大增加了9.98%.
The stead-state CFD simulations model of a RD190 diesel engine in helical inlet ports was established and the flow characteristics were studied. The swirl ratio of cylinder，the flow coefficient of intake ports and the engine performance were calculated. Meanwhile，The influence of the shape of the intake valve stem on inlet flow characteristics in diesel engine was analyzed with the three-dimensional CFD simulation platform. The results indicate that the average flow coefficient and average swirl ratio increase first and then decrease with section ratio increasing. The average flow coefficient change a little in relative to the value of the original program with the section ratio in range of 0.28 to 0.3，and the maximum increase of the average swirl ratio is 9.98%