An adaptive mesh rezoning scheme for moving boundary flows and fluid-structure interaction

Arbitrary Lagrangian-Eulerian (ALE) techniques provide a general framework for solving moving boundary flows and fluid-structure interaction problems. ALE formulations allow freedom of prescribing the fluid mesh velocity which can be independent of the velocity of the fluid particles. A major challenge in ALE descriptions lies in developing mesh moving techniques to update the fluid mesh and map the moving domain in a rational way. Exploiting the notion of arbitrary mesh velocity for the fluid domain, we have developed an adaptive mesh rezoning technique for structured and unstructured meshes. The method has been applied to meshes composed of triangles, quadrilaterals, as well as an arbitrary combination of these two element types in the computational domain. This feature of the proposed scheme is very attractive from practical problem solving viewpoint in that it allows kinematically complex problems to be handled effectively. A variety of test cases are shown that involve single and/or multiple moving objects. Embedding the mesh rezoning scheme in our flow solver, we also present some representative simulations of flows over moving meshes.