An Efficient Local-Time-Stepping Scheme for Discontinuous Galerkin Time Domain for Solving Multiscale Electromagnetic Problems

A novel local-time-stepping (LTS) scheme is introduced into the discontinuous Galerkin time domain (DGTD) method to enhance the efficiency of solving multiscale electromagnetic problems. The proposed LTS scheme partitions mesh elements into a number of classes based on the minimum time step multiplied with the powers of two, whose total time nodes are fewer than the widely-used LTS scheme. Moreover, instead of a backward/forward approximation, an inter/extrapolation approach is exploited for achieving accurate exchange of the electric and magnetic field information at the interfaces between coarse and fine mesh elements at asynchronous time nodes. A series of numerical examples are presented for verification, demonstrating that the proposed LTS scheme outperforms the conventional LTS schemes in addressing multiscale electromagnetic challenges.