An embedded boundary method for an inviscid compressible flow coupled to deformable thin structures: The mediating body method

摘要

This article deals with fast transient phenomena involving fluids and structures undergoing large displacements and rotations, associated with nonlinear local behavior, such as plasticity, damage, and failure. A new approach is proposed to handle the interaction between a structure and the compressible fluid it is immersed into. The equations governing the evolution of the structure and the fluid are discretized using Lagrangian shell finite-elements and Eulerian cell-centered finite volume approaches, respectively. The meshes of the structure and the fluid are totally independent from one another and fully unstructured. The proposed method uses an intermediate body through which the physical quantities are exchanged between the fluid and the structure. It relies on the solution of local one-dimensional fluid-structure Riemann problems in local frames related to the normal of the structure. Since the proposed approach does not require to subdivide the fluid cell according to the structure geometry, it can deal with complex nonmanifold thin structures. Nevertheless, it is shown through some numerical experiments that, thanks to some features described in this article, the method provides accurate results. It is also shown that the method can cope with large 3D problems.