IMPROVED TREATMENT OF INTERSECTING BODIES WITH THE CHIMERA METHOD ANDVALIDATION WITH A SIMPLE AND FAST-FLOW SOLVER

For flow simulations about complex geometries, the chimera overset sch eme provides a conceptually simple method for domain decomposition. At the intersection of two elements, the primary meshes of the elements do not in general yield a good representation of the geometry. It is s hown that 'collar' grid can improve the simulation in these areas. The method is applied to several multi-body configurations. A simple and robust algorithm for steady inviscid flow, in terms of the primitive v ariables, is described for body fitted coordinates. This algorithm has been adapted for the chimera framework for the calculation of flow pa st complex geometries. This method is intended to be used for prelimin ary engineering analysis. The results, for the flow past a sphere, ran ging from low Mach M-infinity = 0.2, to critical flow, M-infinity = 0. 55, show good agreement with the exact potential flow solution. The fl ow about an ellipsoid has also been obtained and a comparison with an implicit Euler scheme has been made. (C) 1998 Elsevier Science Ltd. Al l rights reserved.