Numerical Modelling for Underwater Excavation Process: A Method Based on DEM and FVM

A 3D dynamic numerical model is established for modelling the excavation process for dredging purposes. The interaction between the solid and fluid phases is realized by a specially designed DEM-FVM coupling mechanism, where the fluid-particle interaction forces, the volume fraction information and the particle information are constantly updated and exchanged. Dry and underwater sand cutting simulations are conducted and validated against experimental results. Simulation results of cutting of cohesive soil in atmospheric condition match with the experimental data within acceptable error margin, while the underwater cutting simulations of cohesive soil have not been validated due to the lack of experimental data. Besides, the general applicability of using Discrete Element Modelling (DEM) to create rock samples, and the calibration of DEM rock samples have been investigated, which are essential for conducting atmospheric and underwater rock cutting simulations in the future.