Effect of the liquid density on a liquid-gas-particle mixture flow in dam break

The present study numerically investigated the effect of the liquid density on the liquid-gas-particles mixture flow during dam break using the computational fluid dynamics (CFD) and discrete element method (DEM). The successive validation of the adopted CFD-DEM method was performed by comparison with the results of the previous computational and experimental studies. The density ratio (DR) is defined as the ratio of the liquid density to the particle density, leading to 1.04 <= DR <= 2.5. As DR decreases, the liquid density becomes large and at the smallest DR = 1.04 is as heavy as a particle density. As DR decreases, the motion of the front heads of the liquid and particles becomes faster. The gap between the front head positions of the free surface and the particles becomes larger with decreasing DR. The particle front position is almost proportional to the time without the deflection. However, the time history of the liquid front position was a slightly deflected formation. The time histories of the front head positions of the liquid and particles showed the similar profile, regardless of DR. Thus, we propose empirical models of the normalized front head positions of the liquid and particles as a function of the normalized time based on the present numerical results. (C) 2019 Elsevier Ltd. All rights reserved.