Unstructured Moving Patched-Grid Method Using Concept of Overset Grid

Abstract

From a point of view of grid generation, an overset grid generation method is suitable for a flow around moving complicated-shaped body. The overset grid method treats two grid-types which are a main-grid placed on all over the flow field and a sub-grid placed around the body. However it is difficult to satisfy a physical conservation law since the overset grid method interpolates the value between the main-grid and the sub-grid. To assure the conservation law on the overlapped region, we propose a new method that the overset grid method is combined to the unstructured moving grid finite volume method. In this method the sub-grid and the main-grid are joined by the unstructured grid. The feature of the method is that a control volume on which a space-time unified domain is adopted, and the method assures the geometric conservation law too even if the sub-grid moves and deforms. The method is applied to a problem such that complicated-shaped body flies in supersonic flow.