A changing-topology moving mesh technique for large displacements
Résumé
Three-dimensional real-life simulations are generally unsteady and involve moving geometries. Industry is currently very far from performing such body- fitted simulations on a daily basis, mainly due to the robustness of the moving mesh algorithm and their exten- sive computational cost. The proposed approach is a way to improve these two issues. This paper introduces two new ideas. First, it demonstrates numerically that moving three- dimensional complex geometries with large displacements is feasible using only vertex displacements and mesh- connectivity changes. This is new and presents several advantages over usual techniques for which the number of vertices varies in time. Second, most of the CPU time spent to move the mesh is due to solving the mesh deformation algorithm to propagate the body displacement inside the volume. Thanks to the use of high-order vertex trajectory and advanced meshing operators to optimize the mesh, we can drastically reduce the required number of solutions and CPU time. The efficiency of this new methodology is illustrated on numerous 3D problems involving large displacements.