Application of curved parametric hexahedron in spectral-element time-domain

Curved parametric hexahedron with 20 geometric interpolation nodes is used as basic building block for modeling of 3-D electromagnetic structures of arbitrary shapes in the spectral-element time-domain (SETD) method. By mean of this curved parametric hexahedron, the mass matrix is block-diagonal and the dimension of each block is no more than six. When a central difference scheme is employed for time discretization, an explicit SETD can be obtained because of the inexpensive inversion of the mass matrix. Several numerical results have been shown that the use of this kind of mesh in SETD is right and very effective.