Compressible Fluid-Flow ALE Formulation on Changing Topology Meshes for Aeroelastic Simulations

The analysis of unsteady fluid flows on moving domains is a very complex task, that may be often tackled using domain remeshing techniques. In the present paper a novel mesh movement strategy is presented. It is based on the blending of simple local edge-swapping with mesh deformation by means of the elastic analogy. To deal with mesh topology changes an extension of the classical Arbitary Lagrangian-Eulerian formulation of the fluid flow equations is developed. In this way the use of interpolations of fluid fields between old and new grid is avoided. Furthermore, this extension allows the easy implementation of high order time integration schemes. Preliminary two dimensional numerical simulations are presented to demonstrate the correctness of the present approach. They shows how this approach guarantees a high quality of the grid without resorting to remeshing, resulting in a very efficient solver useful for the analysis of Fluid-Structure Interaction problems, even for the cases which requires large mesh deformations or changes in the domain topology.