CFD在发动机排气歧管设计中的应用

Application of CDF Technology in the Design of Engine Exhaust Manifold

发动机排气歧管的传统设计方法已不能满足现代设计的需求,应用计算流体动力学(CFD)可以深入地了解排气歧管内部的压力和流场分布。文章利用发动机排气歧管气体流动的数学描述及排气歧管三维数值模拟及Fluent软件平台,采用k-ε湍流模型,对排气歧管内部压力和速度的分布情况进行了模拟和分析。结果表明,应用CFD来研究排气歧管和模拟其内部流动状况,计算效率高,容易实现,CFD对优化发动机排气歧管的结构设计和改善排气效果具有很好的指导意义。

The traditional design method cannot meet the requirements of the modern design, but the CFD can give an insight into the inner pressure of exhaust manifold and the distribution of flow field. Adopting the mathematic description of the gas flow of engine exhaust manifold, 3D numerical simulation of exhaust manifold, the software platform of FLUENT and the k-ε turbulent model, this paper simulates and analyzes the inner pressure of the exhaust manifold, the distribution of speed. The results indicate that the CFD technology is of great significance for the structural design of the engine exhaust manifold and the improvement of exhausting performance.