风雪流(简称吹雪)是一种气流挟带着分散雪粒的非典型两相流。风雪流严重影响交通运输、工矿建设和农牧业生产。
Tian Shan is one of the regions with deep snow cover in China. Frequent occurrences of snow drift bring in havoc to communication and transportation, agricultural production and livestock raising.In montane regions, it is rather convienient to study the movement and transport of drifting snow 011 the basis of corrected formula of wind velocitj- distribution. The threshold of the movement of snow particles is related with the physical properties of the particles themselves as well as with the outside environment conditions. In snowy or non-snowy weather, not only the relation between the height of the blowing snow and different kinds of parameters is different, but the strength of drifting snow in layers of various heights is different also. This artiele gives the figures and formula for calculating the unit snow drift quantities of different snow cover density in snowy or non-snowy weather, and discusses the problems of developmental length of snow drift in montane regions.The mechanism of accumulation of drifting snow resulted from the vortex grag-caused hy a sudden change in the curvature of the terrain. As for the road, different fields of flow on different landforms near the roadbed may give rise to different pro-cessess and quantities of drifting snow. Drift accumulation in Tian Shan is mainly located at the leeward or windward, turning and flow circle section, as well as extremely high or low embankment.On the basis of field observation, modelling experiments in the wind tunnel and the effects obtained by means of large scale engineering, we have developed some measures for controlling snow accumulation. In addition, we have proposed "leading", "modifying", "preventing" and "sweeping" as controlling measures, and also discuss the mechanism of some protective measures, their types and their main applications and influencing factors and calculating formulae.