Block alternating splitting implicit iteration methods for saddle-point problems from time-harmonic eddy current models. (Q2864483)

The time-harmonic eddy current model is often used to simulate the electromagnetic phenomena concerning alternating currents at low frequencies. This paper studies the solution for the saddle-point systems that arise from the finite element discretizations of the hybrid formulations of the time-harmonic eddy current problems. By sufficiently utilizing the algebraic properties and the sparse structures of the coefficient matrix, they establish a class of block alternating splitting implicit iteration methods and demonstrate its unconditional convergence. Experimental results shown the feasibility and effectiveness of this class of iterative methods when they are employed as preconditioners for Krylov subspace methods such as GMRES and BiCGSTAB.