Numerical insights into rock-ice avalanche geophysical flow mobility through CFD-DEM simulation

Geophysical flows like rock-ice avalanches have high mobility and destructive potential, causing global loss of life and property. Water, often from melted ice, significantly impacts their mobility. Experimental investigations of debris friction in a rotating drum with melting ice show reduced friction due to water. However, experimental limitations hinder extensive testing. Employing a numerical model can overcome this, facilitating the study of various scenarios in understanding such calamitous geophysical flows. In the current work, we numerically replicate the rotating drum experiment using Eulerian-Lagrangian CFD-DEM coupling. We focus on the initial and final states, considering a 30% gravel and 70% ice mixture (B12-070). We don't model the ice melting; rather, we inject equivalent water over time. Our simulation captures changes in the frictional behavior of the gravel bulk and flow height profile, closely aligning with experimental observations.