四缸发动机排气歧管振动特性及热负荷分析  

Vibration Characteristics and Heat load Analysis of Four-cylinder Engine's Exhaust Manifold

作　　者：索举杨 赵华[1] Suo Ju-yang;Zhao Hua(Nanyang Institute of Technology,Henan Nanyang 473004)

机构地区：[1]南阳理工学院,河南南阳473004

出　　处：《内燃机与配件》2025年第2期18-20,共3页Internal Combustion Engine & Parts

摘　　要：排气歧管是发动机排气系统的重要零部件,工作环境极易发生共振,从而导致排气歧管断裂破坏。排放废气时管道内局部热应力集中也容易使其产生疲劳断裂。本文利用逆向工程获取排气歧管的三维模型,基于有限元对逆向模型做自由模态分析,得到排气歧管的理论模态振型;使用LMS振动测试系统对排气歧管进行模态试验,获得试验模态参数及振型,验证了理论模型的准确性;采用Fluent软件对排气歧管进行流固耦合热负荷分析,求解出了排气歧管的热应变、热变形云图。试验及分析结果可为排气歧管的动态特性、可靠性及结构优化提供理论依据。Exhaust manifold is an important part of the engine exhaust system,and the working environment is prone to resonance,which leads to the fracture of exhaust manifold.When exhaust gas is discharged,the local thermal stress concentration in the pipeline is also easy to cause fatigue fracture.The 3D modeling of exhaust manifold was obtained by reverse engineering in this paper.Based on the finite element method,the free mode analysis of the reconstructed model was made,and the theoretical mode of exhaust manifold was obtained.The LMS vibration test system was used to perform modal tests on exhaust manifold,and the experimental modal parameters and vibration modes were obtained,which verifies the accuracy of the theoretical model.Fluent software was used to conduct fluid structure coupling thermal load analysis on the exhaust manifold,and the thermal strain,thermal deformation cloud map of the exhaust manifold were solved.The test and analysis results can provide theoretical basis for dynamic characteristics,reliability and structural optimization of exhaust manifold.

关 键 词：排气歧管 振动特性 热负荷分析 

分 类 号：TK263.5[动力工程及工程热物理—动力机械及工程]