A Numerical Simulation On The Development Process Of Blowing Snow And The Effects Of Snow Grains Shape On It

Among the many affecting the development process of blowing snow, snow grains shape is one of the factors can not be ignored. In this paper, the drag coefficient of a snow grain was reviewed and investigated for a variety of shapes; numerical model of blowing snow was established; simulation of the development process of blowing snow, analysis and comparison of snow grains number of endurance and snow-transport rate with the change of time, as well as snow-transport rate for five kinds of common snow grains in blowing snow were made. The results showed that: snow grain shape has great influence on snow grain number of endurance and snow-transport rate, may even be orders of magnitude difference. Therefore, snow grains can not simply be seen as the sphere or ellipsoid in blowing snow simulation. The main reason for the difference is that the air resistance exerted on snow grains with different shapes is different even if these grains lift off with the same velocity from the surface. Thus the height they achieve varied widely. For example, the height of a spherical snow grains is approximately three times as long as the height of a star snow grains. Snow grains run higher and will get more energy for the wind energy at high level is much larger than the energy of the wind field at low height.