We present a loosely coupled approach for the solution of fluid-structure interaction problems between a compressible flow and a deformable structure. The method is based on staggered Dirichlet-Neumann partitioning. The interface motion in the Eulerian frame is accounted for by a conservative cut-cell Immersed Boundary method. The present approach enables subcell resolution by considering individual cut-elements within a single fluid cell, which guarantees an accurate representation of the time-varying solid interface. The cut-cell procedure inevitably leads to non-matching interfaces, demanding for a special treatment. A Mortar method is chosen in order to obtain a conservative and consistent load transfer. We validate our method by investigating two-dimensional test cases comprising a shock-loaded rigid cylinder and a deformable panel. Moreover, the aeroelastic instability of a thin plate structure is studied with a focus on the prediction of flutter onset. Finally, we propose a three-dimensional fluid-structure interaction test case of a flexible inflated thin shell interacting with a shock wave involving large * Corresponding author.

In the present work, a monolithic solution approach for thermo-structure interaction problems motivated by the challenging application of the behaviour of rocket nozzles is proposed. Structural and thermal fields are independently discretised via finite elements. The resulting system of equations is solved via a monolithic thermo-structure interaction scheme, which is constructed by a block Gauss-Seidel preconditioner in combination with algebraic multigrid methods. The proposed method is tested for four numerical examples, the second Danilovskaya problem, a simplified rocket nozzle configuration, an internally loaded hollow sphere, and a fully three-dimensional nozzle configuration of a subscale thrust chamber. Good agreement of the numerical results with results from the literature is observed. Furthermore, it is shown that the monolithic solution algorithm can handle the complete range of the parameter spectrum, whereas partitioned algorithms are limited to a certain parameter range only. Moreover, the monolithic algorithm exhibits improved efficiency and robustness compared to partitioned algorithms. describing equilibrium of the forces of inertia, internal and external forces in the structural domain . In this context, , d and R d denote the density, the unknown displacements and accelerations, respectively. O b represents an arbitrary body load. The internal forces are expressed in terms of the stress tensor . For an isotropic thermoelastic solid, the strain-energy function described in the

We present a loosely-coupled approach for the solution of the thermo-fluid-structure interaction problem, based on Dirichlet-Neumann partitioning. A cartesian grid finite volume scheme, with conservative interface method is used for the fluid and a finite-element scheme for the thermo-structure problem. Special attention is given to the transfer of forces, temperatures and to the structural positions. The structural surface is represented by a level set function in the fluid code. The velocity and temperature field required for the coupling are interpolated from structural values on the zero-contour level set surface. Data transfer between the two codes is performed via message passing interface. The proposed method is tested for a cooling-process of a heated metal bar by mean of an external laminar boundary layer flow. Results show that the presented approach is able to handle the complexity of the three-field problem.