类土壤地表颗粒稳态输运的风洞实验研究  

Wind Tunnel Experiment of Equilibrium Transport of Soil-Like Grains

作　　者：邢茂[1] 郭烈锦[1] 张西民[1] 亢力强[1] 顾正萌[1] 

机构地区：[1]西安交通大学动力工程多相流国家重点实验室,西安710049

出　　处：《西安交通大学学报》2005年第11期1282-1286,共5页Journal of Xi'an Jiaotong University

基　　金：国家基础研究发展规划重点资助项目(G2000048702);国家自然科学基金资助项目(10172069)

摘　　要：通过风洞实验研究了由细沙粒和粗粉粒组成的类土壤颗粒的风力输运过程.实验发现沙粒的质量流量廓线与粉粒的质量流量廓线形式完全不同,在对数-线性坐标中沙粒廓线为直线而粉粒廓线呈3次曲线型.发现粉粒的存在对沙粒的质量流量廓线斜率没有影响,只是改变了沙粒的总输沙率.根据粉粒对沙粒输运特性影响的不同,粉粒质量分数存在一临界值,对于本实验中所用材料此临界值为15%.在低于此临界值时,输沙率随粉粒的质量分数的增大而增大;当高于此临界值后,输沙率随粉粒的质量分数的增大而减小.实验中沙波纹的高度和波长随风速及粉粒的质量分数的增大而增大,而当粉粒的质量分数超过15%时沙波纹消失.Aeolian grain transport on the soil-like surface composed of fine sand and silt is measured in a wind tunnel. It is found that the form of mass flux profile of sand is different from that of silt. Mass flux profile of sand is a straight line in log-linear plot but mass flux profile of silt is more like a third power curve, and the silt fraction in the soil-like surface has slight effect on the slope of sand mass flux profile but affects the amount of total sand transport rate. According to the effect of silt on the motion of sand grains, a critical silt mass fraction in the surface layer is revealed. For the grain material during this experiment, the critical value approaches 15%. When the silt mass fraction is below the critical value, sand transport rate increases with silt mass fraction. However, when the silt mass fraction is beyond the level, sand transport rate decreases with silt fraction. And the sand ripples on the surface arise obviously with the increasing silt mass fraction and wind speed, but disappear as silt mass fraction exceeds 15%.

关 键 词：类土壤颗粒 稳态输运 风洞实验 粉粒 

分 类 号：P425[天文地球—大气科学及气象学]