A fast spectral/difference method without pole conditions for Poisson-type equations in cylindrical and spherical geometries
نویسندگان
چکیده
A simple and efficient FFT-based fast direct solver for Poisson-type equations on 3D cylindrical and spherical geometries is presented. The solver relies on the truncated Fourier series expansion, where the differential equations of Fourier coefficients are solved using second-order finite difference discretizations without pole conditions. Three different boundary conditions (Dirichlet, Neumann and Robin conditions) can be handled without substantial differences.
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