发动机进气歧管流场的数值分析

以某发动机进气歧管为研究对象建立三维模型,运用CFD前处理软件Gambit划分网格,建立进气歧管流场模型,在计算流体动力学软件Fluent中分析各缸进气均匀性,进气歧管的进气阻力,进气歧管的内部流场特性。结果清晰显示各歧管的近壁流速、内部流速、表面总压分布情况,并根据分析结果对进气歧管进行了结构优化,改进后的发动机进气歧管在各缸进口减小总压损失、进气阻力、管二流量等方面取得较明显的效果,管四流量得到提高,各进气管不均匀度得到优化。

Numerical simulation on flow field of engine intake manifold

By taking an engine intake manifold as object of study,a three-dimensional model is established.And then the meshing of the intake manifold is done by using the computational fluid dynamics pre-processing software Gambit.Meanwhile the inlet gas uniformity,resistance of inlet,characteristic of the flow field are analyzed by the software Fluent,which result shows clearly the velocity of flow approximate the wall,inside wall and exterior pressure distribution in the manifolds.According to the results of analysis,the structure of the intake manifold is optimized.And significant improvement effect is achieved in reduction of the pressure loss of cylinders,intake gas flow resistance and the flow rate of the second manifold,thus the fourth flow is increased and the flowing non-uniformity is optimized.