进气管内EGR分布的CFD模拟计算

摘要

对于采用EGR技术路线的多缸柴油机,EGR在各缸均匀分布可以确保燃烧质量,降低裸机排放.建立了某六缸国ⅣEGR柴油机进气管三维模型,采用一维和三维模拟软件相结合,对EGR在进气管内的分布进行了流动机理的模拟分析,评估了EGR各种导入方案以及进气管相关零部件结构设计对EGR和空气混合的影响.对模型进行了CFD稳态计算,研究了4种节气门位置对EGR和空气混合的影响.%For multi-cylinder diesel engine with EGR technology, even distribution of EGR in each cylinder can ensure good combustion quality and less raw emission. The intake manifold 3D model of a real 6-cylinder China IV EGR diesel engine was established, and combined with ID and 3D simulation software to simulate and analyze the flow mechanism of EGR distribution in the intake manifold, and assess the effect of different EGR introduction plans and structure design of related components of the intake manifold on EGR and air mixture. CFD steady state computation is made to the model and the effect of four throttle positions on EGR and air mixture is also studied.