Hybrid IE-FVFD Method for Three Dimensional Electromagnetic Scattering Problems

A new algorithm consisted by finite volume frequency domain (FVFD) method and accurate integral equations (IE) radiation boundary condition (BC) is proposed for efficiently calculating electromagnetic fields and scattering problems. In the FVFD, a pseudo time derivative term was added to control equations system. The spatial flux was calculated using Steger-warming splitting scheme. Fully implicit time marching technique was adopted and the equations were solved using lower upper symmetric Gauss–Siedel algorithm. The IE BC algorithm calculates incoming flux on truncated boundary by Franz integral calculation on electric currents equivalence effect surface in grid. This IE BC algorithm is simple and fast, has no convolution, interpolation operation, or extra storage requirements. It only requires intermittent integration operation during loose coupling iteration. Numerical experiments have shown that IE BC has excellent absorption performance compared with traditional Mur BC, and truncated boundary can approach 0.5 times the wavelength distance to the scattering surface. This IE-FVFD hybrid method can accurately simulate various electromagnetic phenomena, greatly reducing calculation region and grid size, and ensuring calculation accuracy while reducing computation complexity and effectively improving calculation efficiency.