AN EFFICIENT TWO-LEVEL PRECONDITIONER BASED ON LIFTING FOR FEM-BEM EQUATIONS
Keywords:FEM-BEM Equations, Lifting Technique, Preconditioner
The system resulting from the coupled Finite Element Method and Boundary Element Method formulations inherits all characteristics of both finite element and boundary element equation system, i. e., the system is partially sparse and symmetric and partially full and nonsymmetric. Consequently, to solve the resulting coupled equation system is not a trivial task. This paper proposes a new efficient lifting-based two level preconditioner for the coupled global system. The proposed approach is applied to solve the coupled systems resulting from the electromagnetic scattering problem and its performance is evaluated based on the number of iterations and the computational time. Traditional methods based on incomplete and complete LU decompositions are used for comparison.
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