柴油机螺旋气道结构对气道性能的影响研究

Study on influence of the helical port geometry on the port performance of a diesel engine

以186FA柴油机螺旋气道为研究对象,基于CFD技术研究气道螺旋室高度和螺旋坡角对气道性能的影响,考察气道流量系数、涡流比及湍动能分布的变化规律。结果表明:整体流量系数没有明显变化;与原模型相比,当螺旋室高度为30 mm和螺旋坡角为75°时,平均涡流比分别增大2.2%和3.2%,且截面湍动能均减小,对应的气道性能整体较好,为186 FA螺旋气道性能的改进提供了参考。

Taking the helical port of 186FA diesel engine as the research object,the influence of the performance of intake port spiral chamber and the angle of spiral slope on intake port performance was studied based on CFD technology.The results showed that there was no significant change in the overall flow coefficient;compared with the original model,when the height of spiral chamber was 30 mm and the angle of spiral slope was 75°,the corresponding average swirl ratio increased by 2.2%and 3.2%,respectively.Meanwhile,the cross-sectional turbulent kinetic energy decreased and the corresponding airway performance was generally better,which provided a reference for improving the performance of 186FA helical port.