Water impact on obstacles using KBC-free surface lattice Boltzmann method

Free-surface flow problems represent an important class of problems in fluid dynamics. They occur in a wide range of applications and they involve many research fields, from naval architecture to civil and environmental engineering. Typical examples of free-surface problems are the wave impact on structures, breaking dams, hydraulic jumps, and many others. Such problems often involve complex geometries and transient regimes. These features, together with the need of tracking the motion of the free surface to properly predict the physical phenomena, make these problems particularly difficult to handle. Therefore, the capability of a computational model to accurately describe the dynamic characteristics of free-surface flows is nowadays extremely attractive. In this work, the breaking dam case with solid obstacle is simulated via a LB free-surface KBC approach. To date, no attempts have been made to simulate free-surface flows by adopting such collision model. This study demonstrates the viability of this approach, which was found to be stable and accurate in the prediction of the fluid flow phenomena under analysis.