低含水率沙床的临界起沙风速  

On the Threshold Wind Velocity of Sand Movement on Sand Bed with Low Water Content

作　　者：邢茂[1] 郭烈锦[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》2003年第3期318-320,327,共4页Journal of Xi'an Jiaotong University

基　　金：国家重点基础研究发展规划项目 (G2 0 0 0 0 4870 2 )

摘　　要：针对目前对风沙起动机制的认识有限的现状 ,采用量纲分析法推导出对湿沙床的起沙有影响的 4个无量纲数 .经分析得到起沙风速与沙床沙粒粒径和沙床粘结力间的数量关系 .通过建立沙床粘结力与含水率、沙粒粒径的关系式 ,得到临界起沙风速与沙粒粒径、含水率间的定量关系式 .认为低含水率沙床的风沙起动风速与颗粒粒径的一次方和沙床含水率的 1/ 4次方成线性关系 。Dimension analysis method is employed to study the sand movement on wet sand bed. Four dimensionless variables which influence the incipient sand movement in wind are deduced. The quantitative relation among the threshold wind velocity of sand movement, sand diameter and the agglutinate stress of sand bed is obtained with the mentioned dimensionless variables. By modeling the form of water between sand particles in wet sand bed, the correlation among agglutinate stress, water content and sand diameter is set up. Accordingly, a discriminant of threshold condition of sand movement on wet sand bed is sought out. In this discriminant, the threshold wind velocity has a linear relation with sand diameter and the fourth root of water content. This result is coincident with the experimental data.

关 键 词：含水率 沙床 临界起沙风速 风沙起动机制 沙粒粒径 沙床粘结力 风沙二相流 

分 类 号：P425.55[天文地球—大气科学及气象学]