NUMERICAL SIMULATIONS OF TSUNAMIS DUE TO A LANDSLIDE OR A SECTOR COLLAPSE

Abstract

 Numerical simulations using an MPS method have been generated to study tsunamis due to a landslide or a sector collapse. In the cases the initial position of the fluid, which falls down a slope and flows into the water, is the same, the tsunami height becomes larger as the density of the fluid is larger, although the tsunami height is not so large when the fluid changes the shape to a flat form on the slope before flowing into the water. On the other hand, in the cases the falling object is a rigid body, the tsunami height becomes larger as the initial potential energy of the rigid body is larger, though the tsunami height is not so large when the wave holds a bore at its front in the propagation after showing a plunging wave. If the specific gravity of the falling fluid is one, the tsunami height near the shore becomes larger as the offshore still water depth is shallower, while in the case the density of the falling rigid body is larger than that of the water, the tsunami height near the shore becomes larger as the offshore still water depth is deeper.