某商用车驾驶室白车身模态分析

Modal Analysis of Commercial Vehicle Cab's Body-in-White

以某商用车驾驶室白车身为原型,利用模态分析方法对其动力学特征参数进行分析.在理论(正问题)和实验(反问题)两个互补的模态分析过程中,利用有限元模型进行理论模态分析,为实验模态分析的实施打下良好基础.分别采用最小二乘复指数法(LSCE)和最小二乘复频域法(LSCF)进行实验模态分析,得到各阶模态振型并对理论分析的结果进行修正.经过两种结果的比较和分析,最终得出准确的模态分析结果并对白车身原型提出改进意见.生产厂商依据改进意见进行工艺改进,通过用户实际使用证实了改进方案的有效性和正确性.

The theory modal analysis（TMA,forward problem） and experimental modal analysis（EMA,inverse problem） methods were both used to analyze the dynamics characteristic parameters of one commercial vehicle cab＇s body-in-white.Finite element modal analysis was carried out to obtain the mode shape and lay down the basis for experimental modal analysis in TMA process.In EMA process,LSCE（Least Squares Complex exponent method） and LSCF（Least Squares Complex Frequency Domain method,commercial name is PolyMAX） methods were used to get the mode shape and modify the TMA results.Based on the comparison among all the results,the accurate conclusion can be reached and the improvement measures can be brought forward to the prototype.The improvement projection was proved to be effective by consumers＇ utilization after manufacturer put it into applications.