Multiple linear system techniques for 3D finite element method modeling of direct current resistivity  

作　　者：李长伟 熊彬 强建科 吕玉增 

机构地区：[1]School of Geoscience and Info-physics,Central South University [2]College of Earth Sciences,Guilin University of Technology

出　　处：《Journal of Central South University》2012年第2期424-432,共9页中南大学学报（英文版）

基　　金：Projects(40974077,41164004)supported by the National Natural Science Foundation of China;Project(2007AA06Z134)supported by the National High Technology Research and Development Program of China;Projects(2011GXNSFA018003,0832263)supported by the Natural Science Foundation of Guangxi Province,China;Project supported by Program for Excellent Talents in Guangxi Higher Education Institution,China;Project supported by the Foundation of Guilin University of Technology,China

摘　　要：The strategies that minimize the overall solution time of multiple linear systems in 3D finite element method (FEM) modeling of direct current (DC) resistivity were discussed. A global stiff matrix is assembled and stored in two parts separately. One part is associated with the volume integral and the other is associated with the subsurface boundary integral. The equivalent multiple linear systems with closer right-hand sides than the original systems were constructed. A recycling Krylov subspace technique was employed to solve the multiple linear systems. The solution of the seed system was used as an initial guess for the subsequent systems. The results of two numerical experiments show that the improved algorithm reduces the iterations and CPU time by almost 50%, compared with the classical preconditioned conjugate gradient method.The strategies that minimize the overall solution time of multiple linear systems in 3D finite element method （FEM） modeling of direct current （DC） resistivity were discussed. A global stiff matrix is assembled and stored in two parts separately. One part is associated with the volume integral and the other is associated with the subsurface boundary integral. The equivalent multiple linear systems with closer right-hand sides than the original systems were constructed. A recycling Krylov subspace technique was employed to solve the multiple linear systems. The solution of the seed system was used as an initial guess for the subsequent systems. The results of two numerical experiments show that the improved algorithm reduces the iterations and CPU time by almost 50%, compared with the classical preconditioned conjugate gradient method.

关 键 词：finite element method modeling direct current resistivity multiple linear systems preconditioned conjugate gradient recycling Krylov subspace 

分 类 号：P631.3[天文地球—地质矿产勘探]