摘要
为解决常规基于离散傅里叶变换的频域边界元法难以解决无阻尼和低阻尼系统瞬态分析的问题,将指数窗口法与频域边界元法相结合,并采用预校正快速傅里叶变换(pFFT)方法加速边界元求解。为进一步提高分析效率,针对频域边界元法所形成的系列线性方程组,提出了一种最小二乘外推法以获得较高精度的迭代初值,可使初始解残差小于10-2,从而显著减少了迭代次数;将新型的子空间回收算法用于频域系列线性方程组的求解,加快了方程组的迭代收敛速度。算例表明,所提出的方法可显著减少频域边界元法的迭代次数,从而提高了计算效率,并有效降低了迭代解法的内存消耗。
The conventional frequency-domain boundary element method （BEM） based on discrete Fourier transform is difficult to complete transient analysis of low damped and undamped systems. To solve this problem, the exponential window method is combined with the frequency- domain BEM, and the precorrected fast Fourier transform （pFFT） is used to aecelerate the frequency-domain BEM analysis. For solving the sequence of linear systems corresponding to the sampling frequeneies with higher efficiency, an extrapolation method is proposed to obtain good initial guesses. In addition, a newly developed Krylov subspaee recycling method is employed to solve this sequence of linear systems. Numerical examples demonstrate a dramatic reduction of iterations, which leads to higher efficieney and smaller memory consuming.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2014年第3期115-120,共6页
Journal of Xi'an Jiaotong University
基金
国家自然科学基金资助项目(11102154
11074201)
教育部高等学校博士学科点专项科研基金资助项目(2010610212009
2011610211006)
关键词
弹性动力学
边界元法
迭代解法
子空间回收
elastodynamics
boundary element method
iterative method
Krylov subspacerecycling
