Fully nonorthogonal higher-order FDTD schemes for the systematic development of 3-D PMVs in general curvilinear coordinates

The efficient construction of reflectionless PML's in 3-D curvilinear coord inates via a new higher-order FDTD methodology, is presented in this paper. By accurately treating the div-curl problem, the technique introduces a hi gher-order rendition of the covariant/contravariant vector theory with gene ralized conventional and nonstandard schemes. Moreover, a mesh expansion al gorithm decreases the absorbers' thickness. in the time domain, the four-st age Runge-Kutta integrator is also invoked, while the wider spatial stencil s are effectively limited by self-adaptive compact operators. Numerical ver ification indicates that the novel PML's offer a serious suppression of dis persion errors and significant savings in the computational burden.