Numerical investigations of dam-break flow impacting on an elastic beam using various FSI coupling algorithms

Abstract

The occurrence of green water and slamming in severe sea conditions can often be simplified as a dam-break problem. The flow characteristics of dam-break are similar with those on a ship’s deck and can result in structural damage. In this study, the fluid-structure interaction (FSI) of dam-break flow impacting on an elastic beam is investigated based on CFD-FEM method. The FSI coupling is solved in a partitioned manner. The fluid field is solved by OpenFOAM and the structure is calculated by self-developed code using FEM. The two-way coupling algorithm has been implemented to update the mesh of the fluid field. An investigation on mesh independence and the comparison of results with other methods have been conducted to validate the simulation results. After that, three types of FSI coupling algorithms have been utilized to examine the impact on both computational accuracy and efficiency. It is studied that the computational accuracy of all three FSI coupling algorithms is in good agreement. The FSI coupling algorithm utilizing weak iteration exhibits excellent performance in terms of both computational accuracy and efficiency. For the strong coupling algorithm, it is crucial to make a rational selection of the outer and inner iteration numbers in PIMPLE loops.