Unconditionally stable ADI-FDTD formulations in nonorthogonal coordinates

This paper has introduced the NADI-FDTD scheme for generalized nonorthogonal coordinates. Like the ADI-FDTD method, which is free from CFL condition restraint, the proposed scheme requires less CPU time and memory. Since the nonorthogonal gridding can model the curved surface accurately, the proposed method is computationally very efficient for complex structures. Numerical simulations will show that the results using the new algorithm have good agreement with those using the NFDTD methods, but substantial computer resources can be saved.