On the solution of poisson's equation on a regular hexagonal grid using FFT methods

Abstract

Abstract An FFT method for solving the discrete Poisson equation on a rectangle using a regular hexagonal grid is described and the results obtained for a model Dirichlet problem are compared with those obtained on a rectangular grid. For a given grid size the results demonstrate that the hexagonal method is more accurate, but rather less efficient, than the usual 5-point method, whereas for comparable accuracy to be achieved by both methods, the hexagonal method was found to be approximately 20 to 30 times faster than the 5-point method for the model problem.