Structured background grids for generation of unstructured grids by advancing-front method

Abstract

A new method of background grid construction is introduced for generation of unstructured grids using the advancing-front technique. Unlike the conventional triangular/tetrahedral background grids that are difficult to construct and usually inadequate in performance, the new method exploits the simplicity of uniform Cartesian meshes and the superiority of the elliptic grid point distribution for unstructured grid generation. The approach is analogous to solving a steady-state heat conduction problem with discrete heat sources. The spacing parameters of grid points are distributed over the nodes of a Cartesian background grid by solving a Poisson equation. To increase the control over the grid point distribution, a directional clustering approach is developed. The new method is convenient to use and provides better grid quality and flexibility. Some sample two-dimensional results are presented to demonstrate the power of the method.