动态测试与边界元法相结合的模态振型参数识别

AN APPROACH LINKING TEST AND B. E. M. ANALYSIS TO IDENTIFY MODAL SHAPE PARAMETERS

试验模态分析中,要获得完整的模态振型,需要在所有自由度方向都进行测量。为了减少测点数以及为了补足某些无法测量的自由度,本文提出用边界元法的解析关系来扩展动态测试的数据。这样,在进行试验模态分析时,就可以减少测点,增加数据平滑性,并且提高数据精度。经过仿真及实例,验证了方法的可行性。

In experimental modal analysis, it is necessary to measure the response data in directions of all degrees of freedom to obtain the complete mode shape information. In order to decrease the number of measurement points and, especially, to complement the data of those degrees of freedom which are unable to be detected, this paper suggests an approach utilising the analytical relations derived by B.E.M. to extend the dynamic measurement data. By use of this method, in experimental modal analysis, we can take less measurement points, increase data smoothness and improve accuracy. Simulations and testing examples verified the feasibility of the method offered.