基于CFD仿真分析的各缸涡流比一致性研究

Study on Swirl Ratio Uniformity Based on CFD Steady Simulation

为满足天燃气发动机第六阶段排放法规要求,对于发动机设计,需保证各气缸涡流比一致性处于比较高的水平。对于两种进气接管结构进行研究,分析不同的设计对发动机各缸涡流比一致性的影响,首先对于对于装配好的三维模型,使用自动网格生成器生成网格,然后通过三维AVL FIRE仿真软件计算得出进气接管、气道及气缸内的气体流场。计算结果发现进气接管走向对各缸涡流比一致性起到了关键的作用。

In order to meet the China Ⅵ vehicle emission standards,it is necessary to ensure that the swirl ratio consistency of cylinder head maintains a relatively high level for Natural gas engine design. In this paper,two kinds of Inlet bend pipe structures are studied and the influence of different designs on the consistency of swirl ratio of each cylinder of the engine is analyzed,first for assembly 3D model,using automatic grid generator to generate grid,and then the gas flow field in the inlet bend pipe,intake port and cylinder was calculated by 3D simulation software AVL FIRE.The calculation results show that the arrangement of the inlet bend pipe plays a key role in the consistency of the swirl ratio of each cylinder.