A MRTD model for calculating lightning return stroke electromagnetic fields

In this paper, we construct a MRTD model in Cylindrical Grids with perfect matched layer (PML), and apply the MRTD method to calculate electromagnetic fields of lightning return stroke. According to the MRTD framework, scaling function of Dubieties wavelet is choosed for fields expansion and discrimination, special consideration are also given for absorption boundary condition. Numerical simulation results show that the MRTD method and FDTD method are consistent in calculating vertical electric field and azimuthal magnetic field. The MRTD method can significantly save both computational memory and CPU time with large gird mesh, as well as good numerical dispersion property.