A Parallel, Black-box Coupling Algorithm for Fluid-structure Interaction

The simulation of multi-physics scenarios, in particular fluid-structure interaction has gained more and more importance in the last years due to increasing accuracy requirements for a large range of applications from biomedical fields to technical design problems. At the same time, this type of simulation has become feasible due to the increased computing power of modern supercomputers. Note that only the combination of a highly accurate and, thus, highly resolved, discretization with the multi-physics model yields more detailed and more realistic results than a simple single-physics simulation. However, modern computing architectures require a good scalability of simulation methods on massively parallel systems. For fluid-structure interactions, if done in a partitioned way using separate fluid and structure codes, in particular the usually applied staggered scheme executing fluid and structure solver one after the other hinders a good scalability. This is due to the in general largely different computational costs of the two solvers. In this paper, we propose two new coupling schemes for an implicit coupling of black-box fluid and structure solvers that execute the two solvers in parallel and still yield good convergence and stability even for incompressible fluids which is shown by means of numerical results for the flow through a flexible tube.