Abstract
A boundary condition for concentration of snow particles at a bottom boundary is necessary to calculate snowdrifts by a numerical analysis model. Either flux type or gradient type boundary conditions are thought to be reasonable. The concept of an entrainment coefficient of snow particle at the bottom is useful. The values of the coefficient are considered to be a function of the density of the flow and the properties of snow particles. In this paper, the functional form of the coefficient is estimated based on the k-ε turbulence model and the distribution of snow particle flux observed at Mizuho station, Antarctica in 2000. The snow entrainment coefficient is two or three order smaller than the sand entrainment coefficient in rivers.The reason is that the specific weight of snow particles in air is much larger than the specific weight of sand that particles in water.
