一种新的有限元模型移频动力缩聚法

将矩阵幂迭代法与移频技术相结合,建立了一种新的结构动力缩聚方法.该方法首先应用矩阵幂迭代法对结构的初始有限元模型进行一次缩聚,计算初始缩聚模型的特征值,然后通过判断低阶特征值的收敛情况确定移频位置,选择合适的移频值,建立移频后的广义特征方程;再根据矩阵幂迭代法迭代计算新的广义特征方程的动力缩聚矩阵,经迭代收敛后得到精确...

A novel dynamic condensation method with shift for finite element models

Combining the matrix power accelerated subspace iteration method with the shift technique, this paper presents a novel structural dynamic condensation method. Firstly, the structural initial finite element model(FEM) is condensed only once by carrying out the matrix power accelerated subspace iteration method, and the eigenvalues of the initial condensed FEM are calculated. Then, the shift place is determined by judging the convergence situation of low-order eigenvalues, and a new general eigen-equation with shift is built after a suited shift cost is chosen. Finally, the dynamic condensation matrix of the new general eigen-equation is calculated iteratively via the matrix power accelerated subspace iteration, and the accurate condensed FEM is obtained after the iteration convergence. The numerical examples show that the presented method is feasible and has the advantage of quicker convergence rate as well as high reduction accuracy.