An Optimized Hole Cutting Approach for Overset Grid Method with Rigid Body Motion in OpenFOAM

Abstract

The overset grid is an effective method to handle the moving boundary problem with complex geometries or massed movement in Computational Fluid Dynamics (CFD) simulations. As a critical part of the method, the Overset Grid Assembly (OGA) determines the point types. Hole cutting is one of the key processes of OGA to find out the hole points, which will not participate in the subsequent calculation of the simulation. However, repeated hole cutting is required when the boundary moves, restricting the assembly efficiency. In this paper, we propose a Block Corresponding Cutting (BCC) method to accelerate the process by reducing the redundancy of hole cutting with Rigid-body motion. Based on the open-source platform OpenFOAM, the experiments demonstrate that, compared with the classic SAM hole cutting method, the efficiency of BCC-based hole cutting is improved by 28.1% on average.