汽车排气系统的流场分析与优化  

Flow Field Analysis and Optimization of Automotive Exhaust System

作　　者：李洪亮[1] 王海洋[1] 王务林[1] 

机构地区：[1]中国汽车技术研究中心

出　　处：《汽车技术》2010年第1期14-17,共4页Automobile Technology

基　　金：国家863计划重点项目(X121轿车集成开发先进技术);中国汽车技术研究中心项目(基于CAE的汽车排气系统优化设计)

摘　　要：给出了某汽车排气系统一维非定常流动的气体动力学方程组和三维模拟数学模型。建立了该汽车排气系统与发动机的联合模型,并利用此模型得到了排气系统进口温度、质量流量、密度等参数。以此作为边界条件,利用三维CFD软件对该汽车排气系统流场进行了模拟,找到了影响排气系统背压的关键结构并进行了优化。结果表明,模拟结果与试验结果吻合性良好,优化后排气系统背压由40.5kPa降至30kPa。Gas dynamics equations of 1D unsteady flow of an automotive exhaust system and 3D simulation mathematics model are proposed in the paper. And a joint model of the automotive exhaust system and engine is established, and with the aid of this model, parameters of the exhaust system such as air inlet port temperature, mass flow, density are obtained. And with these parameters as boundary condition and with three dimension CFD software, flow field of the automotive exhaust system is simulated, and critical structures which affect exhaust system backpressure is found and optimized. The results show that the simulation result is consistent with the test results. After optimization, exhaust system backpressure decreases from 40.5 kPa to 30 kPa.

关 键 词：排气系统 流场 分析 CFD 

分 类 号：U464[机械工程—车辆工程]