3D MPS-DEM SIMULATION OF WAVE GENERATION INDUCED BY GRANULAR COLLAPSE

Abstract

 The generation of waves by the entry of solid particles into water, such as in mountain collapse triggered tsunamis and landslide tsunamis, involves the complex interaction between solid and fluid phases. Wave generation arises from the deformation of the interface when the solid phase enters the fluid phase. The authors previously performed a two-dimensional numerical simulation using an entirely Lagrangian meshfree coupled fluid-sediment interaction solver (MPS-DEM method), which is effective in handling problems including large interface deformations. However, actual landslide tsunamis are three-dimensional phenomena, necessitating a three-dimensional model. In this study, the previous two-dimensional model is extended to a three-dimensional model, and the reproducibility of the wave generation phenomenon caused by the solid phase entering the water is investigated. As principal calculations, simulations of wave generation experiments are performed that involve the collapse of a rectangular particle column and the entering of solid particles with sliding down on a slope. From the calculated results, it is confirmed that the use of an apparent volume correction model is essential to reproducibility, as also shown in the case of 2D calculations, and that the proposed MPS-DEM solver demonstrates satisfactory accuracy for 3D calculations.