Fluid-Structure Interaction: Acceleration of Strong Coupling by Preconditioning of the Fixed-Point Iteration

Abstract

This contribution focuses on partitioned solution approaches in fluid- structure interaction problems. Depending on certain physical parameters of fluid and structure, the fixed-point iteration that is mostly used to strongly couple the dif- ferent solvers in each time step is susceptible to deceleration.We present a method that is able to overcome this effect by a specific preconditioning of the fixed-point iteration. Thus, the full convergence order of the underlying time-discretisation schemes is preserved. As computational example, a benchmark problem from hemo- dynamics is considered where this effect has a particularly strong influence. It turns out that, though a single step of the preconditioned iteration is more expensive, the overall gain in efficiency can be significant.