A laboratory test of the electrification phenomenon in wind-blown sand flux  

作　　者：Ning Huang Xiaojing Zheng 

机构地区：[1]Lanzhou Univ, Dept Mech, Lanzhou 730000, Peoples R China

出　　处：《Chinese Science Bulletin》2001年第5期417-420,共4页

基　　金：the National Outstanding Youth Fund (Grant No. 19725207) and the Natural Science Fund of Gansu Province.

摘　　要：The measured data in the wind-tunnel tests show that the wind-blown sand particles acquired a negative charge when their diameters are smaller than 250 μm and positive charge when their diameters are larger than 500 μm, which confirms Latham’s assumption that the large particles in wind-blown sand flux acquired positive charge while negative charge developed on small ones. In the meanwhile, the measured data also show that the average charge-to-mass ratio for wind-blown sand particles decreases with the increase of the particle diameter and the wind velocity, and increases with the rise of height. The electric field in wind-blown sand flux is mainly formed by the moving charged sand particles. Its direction is vertical to the Earth’s surface and upward, which is opposite to that of the fair-weather field. The electric field increases with wind velocity and height increasing. These experimental results will lay the foundation for developing the theoretical analysis of the electrification phenomenon inThe measured data in the wind-tunnel tests show that the wind-blown sand particles acquired a negative charge when their diameters are smaller than 250 μm and positive charge when their diameters are larger than 500 μm, which confirms Latham’s assumption that the large particles in wind-blown sand flux acquired positive charge while negative charge developed on small ones. In the meanwhile, the measured data also show that the average charge-to-mass ratio for wind-blown sand particles decreases with the increase of the particle diameter and the wind velocity, and increases with the rise of height. The electric field in wind-blown sand flux is mainly formed by the moving charged sand particles. Its direction is vertical to the Earth’s surface and upward, which is opposite to that of the fair-weather field. The electric field increases with wind velocity and height increasing. These experimental results will lay the foundation for developing the theoretical analysis of the electrification phenomenon in wind-blown sand flux.

关 键 词：wind-blown SAND FLUX CHARGED SAND particles AVERAGE CHARGE electric field strength laboratory test. 

分 类 号：V211.74[航空宇航科学与技术—航空宇航推进理论与工程]