A numerical scheme for frontal solution in cooperation with substructure technique for 3D electromagnetic analysis

The wave-front technique is used for the finite element method (FEM) in mechanics and is efficient in the numerical solution of large linear equations. However, it is not so widely used for electromagnetic (EM) analysis since the characteristics of element matrix equations are quite different, or, in other words, the "front" width for calculating an EM problem is larger than that of a mechanics problem, which affects computational efficiency greatly. For example, unlike mechanical FEM, electromagnetic FEM often deals with irregular elements which results in a large value of "front" width for storing element coefficients and is hard to control. The frontal solution is still in limited application in electromagnetic computation, unlike other methods such as iteration methods in numerical schemes. The paper presents the wave-front method combined with a substructure technique for 3D electromagnetic computation; analysis and a numerical example show that it has good accuracy and computing efficiency, while keeping the advantage of being without convergence problems.