SPH simulations of 3D dam-break flow against various forms of the obstacle: Toward an optimal design

Dams are an important part of a country's infrastructure. After the dam breaks, the collision force of the water column, if severe enough, would incur a great deal of destruction and damage and needs to be concerned specially. In this work, 3D dam-break flows against various forms of the obstacle are numerically simulated by the smoothed particle hydrodynamics (SPH) method. In order to tackle boundaries of irregular or curved shapes involved in the obstacle, both wall particles and dummy particles are adopted in SPH, in which dummy particles are arranged by a particle packing algorithm which allows the attainment of a regular particle distribution. To validate the SPH method, 3D dam-break flow against a vertical wall is first simulated, and the SPH results are compared with the experiment and those obtained by other numerical methods. Then, we extend the method to 3D dam-break flows against various forms of the obstacle. A number of challenging numerical examples including 3D dam-break flows against a right-angled obstacle, a sloping obstacle with the angle of inclination α = 60°, 45°, and 30°, and an arc obstacle with the arc angle β = 90°, 60°, and 45° are simulated. The time evolutions of the pressure on the obstacle surface are shown in details. It is demonstrated that the proposed SPH method can handle 3D large-deformation flows with any complex boundaries accurately. The arc obstacle with β = 60° may be selected as one of the optimal forms of the obstacle for reducing the collision force of the fluid after the dam breaks. The maximum pressure on this obstacle surface is less than ~40% of a right-angled obstacle.