Effect of the bottom material capture and the non-Newtonian rheology on the dynamics of turbulent downslope flows

Abstract

The paper is devoted to the mathematical modeling of naturally occurring downslope flows, such as snow avalanches, mudflows, and rapid landslides. The medium in motion is modeled as a non- Newtonian fluid, the non-Newtonian fluids of different types corresponding to different-in-nature flows. It is taken into account that the downslope flows capture the slope material and entrain it into the motion. The flow is assumed to be turbulent and the Lushchik–Pavel’ev–Yakubenko three-equation turbulence model is used. It is so generalized that it allows for flow unsteadiness, complicated rheological properties, the presence of a free boundary, and the mass transfer at the lower flow boundary. The effect of the bottom material capture and the nonlinear rheological properties of the medium in motion on the flow dynamics is numerically investigated.