Calculating 2D Helmholtz equation based on multigrid method and application in magnetotelluric modeling
Yang Zhenwei1,2, Feng Lei1,2, Zhao Ning3, Zhao Qiufang1,2, Yang Shuang'an1,2
1. Institute of Resources & Environment, Henan Polytechnic University, Jiaozuo, Henan 454000, China;
2. Collaborative Innovation Center of Coalbed Methane and Shale Gas for Central Plains Economic Region, Henan Province, Jiaozuo, Henan 454000, China;
3. College of Computer Sciences and Technology, Henan Polytechnic University, Jiaozuo, Henan 454000, China
Abstract：In order to enhance the computational efficiency and accuracy of Helmholtz equation,we discuss in the paper 2D Helmholtz equation calculation with multi-grid method and other methods such as conjugate gradient (CG),preconditioning conjugate gradient (PCG),and successive over relaxation (SOR).Delaunay triangular mesh algorithm with mesh refinement is automatically adopted in mesh subdivision.Research results show that the multi-grid method has great advantage in computation time consuming and iterative convergence efficiency,but its computational error is larger than the other algorithms.This might be caused by irregular grid subdivision,which is related with interpolation and restriction operator.Finally,a preliminary test on 2D magnetotelluric modeling with multi-grid algorithm is shown in the paper.
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