Particle shape effects on submarine landslides via CFD-DEM

Abstract

Submarine landslides constitute a crucial area of interest in the fields of geotechnical and oceanic research. These events are often simplified as a granular collapse process that occurs underwater. This study focuses on incorporating the complex particle shape factor into computational fluid dynamics-discrete element method (CFD-DEM) simulations to investigate submarine granular collapse. Both dry and submarine tests are conducted to validate the numerical results against experimental observations. The study then summarizes the relationship between the final deposit state and the initial aspect ratio of the specimen for submarine tests. The numerical approach is used to examine the impact of particle shape on submarine granular collapse, with three key features (aspect ratio, angularity, and roughness) of polyhedral particles studied in terms of their dynamic processes and final deposit profiles. Finally, the proposed CFD-DEM coupling approach is leveraged to analyse the evolution of granular force fabric and the distribution of excess water pressure for different particle shapes.