Momentum profile of aeolian saltation cloud  

作　　者：ZhiBao Dong WanYin Luo GuangQiang Qian HongTao Wang 

机构地区：[1]Key Laboratory of Desert and Desertification,Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou,Gansu 730000,China

出　　处：《Research in Cold and Arid Regions》2009年第1期25-29,共5页寒旱区科学(英文版)

基　　金：the funding from the Natural Science Foundation of China (40638038);the Knowledge Innovation Project of the Chinese Academy of Sciences (KZCX3-YW-329)

摘　　要：The momentum profile of an aeolian saltation cloud is poorly understood. In this paper, height profiles for saltation momentum are reconstructed for three particle-size populations at four wind velocities based on profiles for mean particle velocity and relative particle concentration of saltation cloud obtained using particle image velocimetry in a wind tunnel. The results suggest that the saltation momentum profiles are characterized by peak curves with a maximum at some height above the surface. The height of this maximum increases with increasing wind velocity, but decreases with increasing particle size. It is linearly correlated with average saltation height and is comparable with the results of numerical simulations in a previous study. Our results confirm that Bagnold’s kink is an important feature of wind velocity profiles modified by the presence of saltating particles and that the height of the kink is closely related to the average trajectories of the saltating particles.The momentum profile of an aeolian saltation cloud is poorly understood. In this paper, height profiles for saltation momentum are reconstructed for three particle-size populations at four wind velocities based on profiles for mean particle velocity and relative particle concentration of saltation cloud obtained using particle image velocimetry in a wind tunnel. The results suggest that the saltation momentum profiles are characterized by peak curves with a maximum at some height above the surface. The height of this maximum increases with increasing wind velocity, but decreases with increasing particle size. It is linearly correlated with average saltation height and is comparable with the results of numerical simulations in a previous study. Our results confirm that Bagnold’s kink is an important feature of wind velocity profiles modified by the presence of saltating particles and that the height of the kink is closely related to the average trajectories of the saltating particles.

关 键 词：aeolian saltation cloud momentum profile wind tunnel test 

分 类 号：P931.3[天文地球—自然地理学]