TECHNICAL NOTE: IMMERSED BOUNDARY METHOD (BODY FORCE) FOR FLOW AROUND THIN BODIES WITH SHARP EDGES

Efficient methods to identify immersed boundary nodes and handling of thin bodies with sharp edges are introduced as an improved immersed boundary method. Particular attention is focused on the treatment of interaction with thin structure and near the trailing edge. It is applied to 2-D flow fields involving fixed rigid object. The immersed boundary method uses a body force proportional to a solid volume fraction to couple the motions of solid and fluid at the interface. The improved method is proved to be applicable to various arbitrary objects including those with thin profile and sharp edges. The present method is applied to a uniform flow field around a rigid 2-D thin airfoil. The computational results had shown the capability of the method to solve the complexity faced by this geometry and also other arbitrary shaped objects.