旋转对称结构制动盘模态相关性分析

Modal correlation analysis for brake disc of rotationally periodic structures

为了消除具有旋转对称特性的制动盘重根模态对模态相关性Cross MAC值计算带来的误差,进行了制动盘的试验模态分析和有限元模态分析,提取相应的模态参数,在此基础上采用巡回群和初等旋转变换重置模态振型矢量。重置后的试验模态与有限元模态的前9阶Cross MAC值均接近1,准确的反映了二者之间的相关程度。表明巡回群和初等旋转变换二种方法对改善旋转对称结构的模态振型相关分析都是行之有效的。

To eliminate errors influence of repeat modal shape solutions of brake disc with rotation symmetry characteristic on calculation of cross modal assurance correlation （ Cross MAC） , the experimental modal analysis and finite element modal analysis for the brake disc were performed to identify each corresponding modal parameter. On this basis, the vectors of modal shape were reset utilizing cyclic group and elementary rotation transformation. Further, the correlation analysis results of the finite element modal analysis and experimental modal analysis showed that the values of Cross MAC of the first nine modes are close to 1, they reflect correctly the correlation level among the modal shape vectors of the brake disc; the two modal shape vector reset methods of cyclic group and elementary rotation transformation are effective to the modal correlation analysis for brake disc of rotationally periodic structures.