高风速下沙粒跃移跃距的实验研究

跃距是颗粒运动的重要参数之一,沙粒跃距的实验研究对沙粒跃移理论研究有重要的参考意义.由于高风速下沙粒跃移轨迹平缓,飞行距离较长,因而,高风速下沙粒跃距的实验研究很少.通过对沙粒跃移特点进行分析,提出同时采用水平集沙仪和垂直集沙仪观测沙粒跃距的方法,并采用该方法对高风速下沙粒跃距进行野外观测研究.结果表明,沙粒跃距随粒径减小呈指数规律增大,沙粒粒径与运动方式转换趋势与前人研究结果基本一致,说明该方法测量沙粒跃距是可行的.

Experimental Study on the Maximum Path Length of Sand at High Wind Velocity

The maximum path length is one of the important parameters on wind-blown sand movement and the experimental study of maximum path length may provides important reference for the theory study on saltation movement of sand grain.For the reason that he track of saltation sand grain is very flat and the maximum path length is longer at high wind velocity,the experimental study on maximum path length at high wind velocity is scarce.An experimental method by using the horizontal array trap and the vertical array trap together is introduced based on the characteristic of grain saltation movement in this paper.According to the above method,the maximum path length of saltating sand grain was measured in the field under the high wind velocity situation.The results show that maximum path length has the exponential type increase tendence along with the decrease of the grain size,and the transition trend and movement manner of grain size shows the satisfactory agreement to the previously studies which indicate that it is feasible to measure the maximum path length of saltation sand by using this method.