Evaluation Index of Acceleration Factor and Ordering in Shifted ICCG Method for Electromagnetic Field Analyses

This paper introduces a simple evaluation way for preconditioning effects in the shifted ICCG method. Since the proposed evaluation index is easily calculated with little additional memory requirement in an incomplete factorization process, it can be used for setting appropriate parameters of the solver, such as an acceleration factor and ordering of unknowns, prior to a time-consuming iteration process. Numerical results show that the evaluation index gives a good estimate of number of iterations necessary for convergence