【作者】 舒爱梅； 韩强； 翁建生； 余文杰； 李继伟；

【Author】 SHU Aimei;HAN Qiang;WENG Jiansheng;YU Wenjie;LI Jiwei;Suzhou Automotive Research Institute,Tsinghua University;College of Power and Energy Engineering,Nanjing University of Aeronautics and Astronautics;

【机构】 清华大学苏州汽车研究院； 南京航空航天大学能源与动力学院；

【摘要】 为研究热机载荷对排气系统振动特性与疲劳寿命的影响,本文提出了一种基于名义应力法的汽车排气系统振动热疲劳寿命预测的方法。该方法利用有限元软件搭建整个包含动力总成的系统仿真模型并经试验校准,采用双向流固耦合分析得到系统固体温度场分布,并研究温度场对系统热模态及疲劳寿命影响;结果表明,在温度场作用下结构模态振型基本不变但模态频率降低,并且常温寿命为热疲劳寿命的近1000倍,可见温度载荷作用不可忽视。本文总结出一套在设计阶段有效评估排气系统振动疲劳寿命的方法,有效缩短开发周期并降低疲劳破坏风险。更多还原

【Abstract】 In order to study the influence of thermal load and mechanical load on the vibration characteristics and fatigue life of the exhaust system,this paper proposes a method based on nominal stress method for predicting vibration thermal fatigue life of automotive exhaust system.The method is based on the finite element software to build the whole system simulation model including the powertrain and is calibrated by modal experiment The fluid-solid coupling analysis is used to obtain solid temperature field distribution of the system and the influence of temperature field on the thermal mode and fatigue life of the system is studied.The results the temperature load has significant effects on vibration characteristics and fatigue life.This paper summarizes an effective method which effectively shorten the design phase of the development cycle and reduce the risk of fatigue damage.更多还原