基于OptiStruct的某车型排气系统有限元分析  

Finite element analysis of a vehicle exhaust system based on OptiStruct

作　　者：黄大伟 田永康 谢华林 龚运息[1] HUANG Dawei;TIAN Yongkang;XIE Hualin;GONG Yunxi(School of Mechanical and Automotive Engineering,Guangxi University of Science and Technology,Liuzhou 545006,China)

机构地区：[1]广西科技大学机械与汽车工程学院,广西柳州545006

出　　处：《广西科技大学学报》2021年第4期22-27,共6页Journal of Guangxi University of Science and Technology

基　　金：柳州市科技计划项目(2019BA10601)资助.

摘　　要：排气系统作为重要的发动机部件,对发动机性能和噪声都有极大的影响.为提高汽车安全性和乘坐舒适性,优化排气系统的设计,根据相关设计要求对排气系统进行了强度和模态分析.首先基于CATIA软件,建立排气系统的三维模型;再用Hypemesh软件进行网格划分、简化模型、施加约束等操作,通过OptiStruct求解器对排气系统进行1 G静力分析、4 G静力分析、约束模态分析.仿真结果显示,排气系统在1 G下的位移和支反力均在设计要求范围内;4 G下的最大应力位于第一挂钩处,远小于150 MPa;约束模态分析了排气系统在200 Hz内的23阶模态,并重点关注了发动机怠速激励频率附近的模态.计算的排气系统固有频率都不在发动机怠速时的激励频率区间内,故排气系统不会与发动机发生共振现象,满足设计要求.Exhaust system as an important engine parts has great influence on engine performance and noise.The paper optimizes the exhaust system for vehicle ride comfort and safety.According to the relevant design requirements,the exhaust system strength and modal analysis are performed.Firstly,the three-dimensional model of exhaust system of a vehicle model is modeled by CATIA.Then,HyperWorks is used to divide the grid to simplify the model and perform other operations.Static analysis of exhaust system at 1 G and 4 G forces and constraint modal analysis of exhaust system are based on OptiStruct solver.The simulation results show that the displacement and support force of the exhaust system at 1 G are within the design requirements;the maximum stress at 4 G is located at the first hook,far less than 150 MPa;The constrained mode analysis of 23 modes of the exhaust system at 200 Hz focuses on the modes near the engine idling excitation frequency.The calculated natural frequencies of the exhaust system are not in the excitation frequency range when the engine is idling,so the exhaust system will not have resonance with the engine,which meets the design requirements.

关 键 词：排气系统 有限元 OptiStruct 模态分析 

分 类 号：U464.134.4[机械工程—车辆工程]