基于复模态实验数据的陀螺矩阵的修正

在实际工程中,由有限元模型得到的计算值与通过试验获得的测量值之间往往存在偏差。为了能够精确预测结构的动力响应,依据测量信息修正存在的动力模型是非常必要的。本文考虑用不完备复模态实验测量数据修正陀螺矩阵的问题。在假定分析质量矩阵Ma>0与刚度矩阵Ka>0是精确的情况下,通过求解一个约束最优化问题,运用Lagrange乘子法得到了满足特征方程的加权Frobenius范数意义下的最优反对称修正矩阵。

Updating of Gyroscopic Matrix Based on Incomplete Measured Complex Modal Data

There is a gap between the prediction resulting from the finite element model and experimental results from the test model or actual structure.Updating the existing dynamic model based on the measured modal data is very important to predict the actual behavior of the structure precisely via the structural dynamic model.The analytical mass matrix,M_a>0,and stiffness matrix,K_a>0,are assumed correct and only the gyroscopic matrix needs to be updated.By solving a constrained optimization problem in virtue of the Lagrange multiplier method,the optimal corrected gyroscopic matrix complied with the required eigenvalue equation is found under a weighted Frobenius norm sense.