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.
