A cut-cell finite volume - finite element coupling approach for fluid-structure interaction in compressible flow

摘要

We present a loosely coupled approach for the solution of fluid-structureinteraction problems between a compressible flow and a deformable structure.The method is based on staggered Dirichlet-Neumann partitioning. The interfacemotion in the Eulerian frame is accounted for by a conservative cut-cellImmersed Boundary method. The present approach enables sub-cell resolution byconsidering individual cut-elements within a single fluid cell, whichguarantees an accurate representation of the time-varying solid interface. Thecut-cell procedure inevitably leads to non-matching interfaces, demanding for aspecial treatment. A Mortar method is chosen in order to obtain a conservativeand consistent load transfer. We validate our method by investigatingtwo-dimensional test cases comprising a shock-loaded rigid cylinder and adeformable panel. Moreover, the aeroelastic instability of a thin platestructure is studied with a focus on the prediction of flutter onset. Finally,we propose a three-dimensional fluid-structure interaction test case of aflexible inflated thin shell interacting with a shock wave involving large andcomplex structural deformations.