Grid adaptation using a distribution of sources applied to inviscid compressible flow simulations

Abstract

AbstractUnstructured tetrahedral grids are generated using a new, very efficient procedure based upon the Delaunay triangulation. The generation procedure is extremely fast, having the capability to generate large grids in minutes on workstations. To maximize this computational performance, a new form of adaptivity has been developed involving the use of sources placed within regions of the domain which require further grid point resolution. A source has a position and a specified grid point density. An error indicator is used to find the elements within the grid which require refinement. Within such elements sources are placed with specified grid point densities which are proportional to the amount of refinement required. The grid generation procedure is then invoked and a grid generated whose grid point density is controlled by the sources. The resulting grid is thus refined in the regions identified by the error indicator as requiring greater resolution. The paper discusses the generation process and emphasizes the new solution adaptation capability. Several examples of the approach are given, including aerospace compressible flow simulations over realistic configurations.