Efficient numerical methods for partitioned fluid-structure interaction simulations

Fluid-structure interaction simulations are crucial for many engineering problems. For example, the blood flow around new heart valves or the deployment of airbags during a car crash are often modeled with fluidstructure interaction simulations. Also, to design safe parachutes, simulations are carried out to model the unsteady deformations of the parachute during a jump. Thus, there is an apparent need for multi-physics software codes which can model fluid-structure interaction problems. However, current state-of-the-art solvers cannot be used for design or optimization studies of for example aircraft structures due to long simulation times. This is mainly caused by a large number of coupling iterations needed to reach convergence within each time step for a strongly coupled fluid-structure interaction simulation. Also, a large number of time steps are required to reach an acceptable accuracy in time for unsteady simulations. Hence, there is an urgency for efficiency improvements of fluid-structure interaction solvers. In this thesis, two approaches are investigated to decrease the computational times for a fluid-structure interaction simulation: multi-level acceleration of the coupled problem, and the use of higher order time integration schemes.