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

• 作 者: LI Chang-wei XIONG Bin QIANG Jian-ke L(ü) Yu-zeng
• 机 构: School of Geoscience and Info-physies, Central South University, Changsha 410083, China; College of
• 出 处: 中南大学学报（英文版）
• 发表日期: 2012年2期
• 关键词: finite element method modeling direct current resistivity multiple linear system

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.