摘要
为探寻有效的随机振动下橡胶隔振器疲劳寿命计算方法,以某电动汽车空调压缩机橡胶隔振器为研究对象,开展隔振器路谱采集试验,获得隔振器主动端的加速度时间历程信号。利用傅里叶变换方法将加速度信号转变为加速度功率谱密度,以加速度功率谱密度作为载荷输入,在变温恒湿环境下开展了压缩机橡胶隔振器的随机振动试验,观察到橡胶隔振器主簧部位出现开裂现象。建立了橡胶隔振器的有限元模型,开展了静态特性试验,静态刚度仿真值与试验值相对误差在±5%以内,验证了有限元模型的有效性。利用ABAQUS进行了单位载荷下橡胶隔振器的频率响应分析,提取橡胶单元应力响应功率谱密度并导入Fe-safe中,以加速度功率谱密度为载荷输入,计算隔振器的疲劳寿命,计算结果与随机振动台架试验结果的相对误差仅为2.5%,并可有效预测橡胶隔振器橡胶单元的疲劳危险位置。最后,通过对橡胶隔振器进行结构改进,使其疲劳寿命延长至改进前的2.8倍,满足了疲劳寿命设计要求。该文研究结果有利于缩短橡胶隔振器的产品设计周期,降低样件试验成本。
In order to effectively calculate the fatigue life of rubber vibration isolator under random vibration loads,a rubber vibration isolator for air conditioning compressor of an electric vehicle was taken as the research object,and the road spectrum acquisition of rubber vibration isolator was carried out,by which the acceleration signals versus time of rubber vibration isolator were obtained.Then,Fourier transform was used to transform the acceleration signals into the acceleration power spectral density as load input,and a random vibration test of rubber vibration isolator for compressor was carried out under variable temperature and constant humidity conditions,with the cracking of main spring of rubber vibration isolator being observed.Moreover,a finite element model of rubber vibration isolator was established,with its validity being verified by static characteristic tests as the relative error between simulation value and test value is within±5%.In addition,frequency response of rubber vibration isolator under unit load was analyzed by ABAQUS,that is,extracting and importing stress response PSD of rubber element into Fe-safe,and using acceleration PSD as load input to calculate the fatigue life.The calculated results were compared with the random vibration test results,finding that the predicted life is consistent with test data,with a relative error of only 2.5%,and that fatigue danger position of rubber vibration isolator unit can be effectively predicted.Finally,the structure of rubber vibration isolator was improved,through which the fatigue life of rubber vibration isolator is 2.8 times that before the improvement,meaning that the fatigue life design requirements are successfully met.This study helps to shorten the design cycle of rubber vibration isolator and reduce the cost of sample test.
作者
李旻
姚棋水
LI Min;YAO Qishui(School of Mechanical and Automotive Engineering,South China University of Technology,Guangzhou 510640,Guangdong,China)
出处
《华南理工大学学报(自然科学版)》
CSCD
北大核心
2024年第12期14-21,共8页
Journal of South China University of Technology(Natural Science Edition)
基金
国家自然科学基金资助项目(12272137)。
关键词
橡胶隔振器
疲劳寿命
有限元分析
耐久性试验
功率谱密度
rubber vibration isolator
fatigue life
finite element analysis
durability test
power spectral density
作者简介
李旻(1974-),男,博士,教授,主要从事机械设计理论研究。E-mail:limin@scut.edu.cn。
