Efficiency Improvement of Strongly Coupled Fluid-Structure Interaction Simulations: Combining Quasi-Newton and Multi-level Algorithms on Coupling Partitioned Solvers

Despite advances in computational power and numerical algorithms, efficiency and stability issues remain in the simulation of very strongly coupled Fluid Structure Interaction problems. These problems are typically solved with partitioned solution techniques. To improve the coupling of these solvers, Quasi-Newton methods are used. The Aitken method calculates an average underrelaxation parameter for the entire interface. The Least-Squares method calculates an underrelaxation matrix as a linear combination of states and residuals of previous iterations. Another method to improve the e_ciency of strongly coupled problems is multi-level acceleration. The computational workload is reduced when iterations are done on a coarser grid.Aerospace Engineerin