Acoustic sensor to measure snowdrift and wind velocity for avalanche forecasting

Abstract

A new mathematical model of slushflow dynamics is developed. A slushflow is treated as a two-layer flow. The lower layer consists of pure liquid phase (water) and the upper layer is a floating water saturated snow (slush). The equations of mass and impulse conservation for each layer are written. These equations include an interaction and mass exchange between the layers and between the water or slush layer and snow cover. The model equations were integrated numerically according to a developed for PC program. Series of numerical experiments for uniform slope were carried out. The structure and dynamics of slushflow were investigated. The dependencies of depths, velocities of flow and front coordinates of the upper and the lower layers on the parameters of the model are established. These parameters are the coefficient of snow entrainment, the coefficient of dry friction, the coefficients of turbulent friction, the discharge of water feeding at the rear end of flow, the snow cover thickness and the slope angle. An effect of exhaustion of the water layer is revealed. This effect is due to fast water absorption by entrained masses of snow.