Time accurate simulation of viscous flow around deforming bodies using overset grids
Petri Fast, William D. Henshaw · 15th AIAA Computational Fluid Dynamics Conference · 2001
Dynamically evolving boundaries and deforming bodies interacting with a flow are commonly encountered in fluid dynamics. However, the numerical simulation of flows with dynamic boundaries is difficult with current methods. We propose a new method for studying such problems. The key idea is to use the overset grid method with a thin, body-fitted grid near the deforming boundary, while using fixed Cartesian grids to cover most of the computational domain. Our approach combines the strengths of earlier moving overset grid methods for rigid body motion, and unstructured grid methods for flow-structure interactions. Large scale deformation of the flow boundaries can be handled without a global regridding, and in a computationally efficient way. In terms of computational cost, the generation of an overset grid is significantly cheaper than a full regridding of an unstructured grid for the same domain, especially in three dimensions. As a computational example, we consider two-dimensional incompressible flow past flexible filaments with prescribed dynamics.