Saltation and suspension of wind-blown particle movement  

作　　者：WANG Ping ZHENG XiaoJing HU WenWen 

机构地区：[1]Key Laboratory of Mechanics on Disaster and Environment in Western China,Ministry of Education,Lanzhou University,Lanzhou 730000,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2008年第10期1586-1596,共11页中国科学：物理学、力学、天文学（英文版）

基　　金：Supported by the Key Project of the National Natural Science Foundation of China (Grant No. 10532040)

摘　　要：Several factors that affect the trajectories of sand particles in a wind-blown sand flux are analyzed by considering the stochastic movement of sand particles transported within turbulent flow in the atmospheric boundary layer. The results show that there are remarkably different trajectories for particles with the same diameter, the same vertical liftoff velocity from sand bed and the same friction ve-locity of wind because of the presence of turbulence flow. The vertical fluctuating velocity of sand particles can be regarded as a reflection of the transport mode, which is related to not only the diameters and liftoff velocity of sand particles but also the shear stress velocity of wind. The critical liftoff velocity and the fraction of each transport mode are calculated for the given particle diameter and friction ve-locity of wind. A comparison of the predicted fraction and the statistical fraction with and without the wind-sand couple effect is made.Several factors that affect the trajectories of sand particles in a wind-blown sand flux are analyzed by considering the stochastic movement of sand particles transported within turbulent flow in the atmospheric boundary layer. The results show that there are remarkably different trajectories for particles with the same diameter, the same vertical liftoff velocity from sand bed and the same friction velocity of wind because of the presence of turbulence flow. The vertical fluctuating velocity of sand particles can be regarded as a reflection of the transport mode, which is related to not only the diameters and liftoff velocity of sand particles but also the shear stress velocity of wind. The critical liftoff velocity and the fraction of each transport mode are calculated for the given particle diameter and friction velocity of wind. A comparison of the predicted fraction and the statistical fraction with and without the wind-sand couple effect is made.

关 键 词：WIND EROSION SALTATION SUSPENSION STOCHASTIC model CRITERION 

分 类 号：P425.2[天文地球—大气科学及气象学]