求解循环对称结构的伪单元法

 对于循环对称结构的求解,在引入循环对称条件时,需对有限元总刚进行行变换和列变换,这将改变总刚的带宽和非零元素的位置。本文提出了求解循环对称结构的伪单元法,用三种伪单元实现上述各变换项的改变量,无需形成完整的总刚矩阵,从而大大地提高了计算机的解题能力。文中用算例进行了说明。

PSEUDO-ELEMENT METHOD (PEM) FOR SOLVING CYCLIC SYMMETRIC STRUCTURE

For the solution of a cyclic symmetric structure, the stiffness matrix of the finite element equations has to carry out the elementary operation as inserting the cyclci symmetric condition. The elementary operation will hange the band-widths and positions of non-zero elements in the stiffness matrix. A Pseudo-element Method (PEM) is presented in this paper for solving the cyclic symmetric structures. In the present method, three kinds of pseudo elements are devised to consider the changes in stiffness matrix during the elementary operations. In the case , the stiffness matrix for the whole structure need not be assembled and the frontal solution program may be directly used. This can greatly reduce the computer in-core storage and CPU time. The calculated results show, in comparison with those of elastic theory, that PEM is an effective and reliable method.