Simulation of Solid-Liquid Interaction in Presence of a Free Surface

In this study, a numerical algorithm is developed for simulating the interactions between a liquid and solid object in presence of a free-surface flow. The presented model is that of the fast-fictitious-domain method integrated into the volume-of-fluid (VOF) technique used for tracking the free surface motion. The developed model considers the solid object as a fluid with a high viscosity resulting in a rigid motion of the object and solves the governing equations everywhere in the computational domain including the solid object. In this methodology, the application of the no-slip condition on the solid-liquid interface and the evaluation of the acting forces on the solid object are performed implicitly. The developed model is validated by a comparison of the simulation results with those of the available experiments in the literature for the free fall of one and two circular disks in a liquid domain and a sphere during its entry into a more dense liquid through a free surface. For all cases considered, the results are in good agreement with those of the experiments and other numerical studies. The model is then used to simulate the complex liquid-solid interaction during the entry of a spinning disk into a liquid free surface.