柴油机排气歧管流场分析与结构优化

Flow Field Analysis and Structure Optimization of Diesel Engine Exhaust Manifold

建立了柴油机排气歧管的三维结构模型,并应用计算流体动力学软件分析流场。描述了排气管中的典型流动,并根据计算结果对排气管进行了优化。优化后的排气歧管模型内腔容积减小,管内部分漩涡消失,流通阻力减小,各缸流量均匀性提高。

A three-dimensional exhaust manifold model of diesel engine was developed. The air-flow in it was analyzed using Computational Fluid Dynamics （CFD） software. Typical flow patterns in the exhaust manifold was presented, and its structure is optimized according to the results of calculation. The inside volume of the optimized exhaust manifold decreased, and some eddies in it disappeared, flow resistance decreased and the uniformity degree of flow between each cylinder increased.