关键词: Lanczos算法, 模态重分析, 拓扑优化, 频率优化

Abstract:

In topological optimization,the structures were often required to make some modifications,and it was very important for improving the effciency of optimization that the low-order eigenvalues could be calculated accurately and quickly. The Lanczos-based modal reanalysis method was applied to topological modification.The presented method which combined Lanczos  algorithm and projection techniques,solved the natural frequency and mode shapes for the modified structures utilizing the already obtained eigenvectors with reduced-basis algorithm.The major advantages laid that the fast convergence of Lanczos vector and high-accuracy of reduced-basis method based on global approximations.A stiff frame example was demonstrated the high accuracy of the reanalysis method.The optimization results of the clamped square plate and vehicle frame indicate that the method can also ensure the calculation accuracy and optimization iteration speed to a certain extent.

Key words: Lanczos algorithm, modal reanalysis, topological optimization, frequency optimization