紫色土坡面细沟流的水动力学特征试验研究  

Study on Hydrodynamic Characters of Rill Flow on Purple Soil Slope

作　　者：任熠[1] 王先拓[1] 王玉宽[1] 傅斌[1] 王勇强[1] 

机构地区：[1]中国科学院水利部成都山地灾害与环境研究所

出　　处：《水土保持学报》2007年第6期39-42,46,共5页Journal of Soil and Water Conservation

基　　金：国家自然科学基金(40771123);国家"973"项目(2003CB415202)

摘　　要：通过不同坡度、流量的组合放水冲刷试验,对紫色土坡面细沟侵蚀发生过程中的坡面细沟流水动力学特征进行了研究。结果表明,在试验的坡度和流量范围内,紫色土细沟流流速随放水量的增加而增大,而在相同放水量下紫色土坡面细沟流流速随坡度增加变化趋势不明显。紫色土细沟流的雷诺数变化于500～4600之间,流态基本属于紊流,在同一坡度下,雷诺数随放水量的增大而迅速增大。紫色土细沟流弗汝德数在整个试验过程中均大于1,属于急流范畴。坡面流阻力系数的大小与水流雷诺数有关,但其变化趋势受坡度和流量的影响。在坡度较缓时阻力系数随雷诺数的增大而减小,在坡度较大时阻力系数随雷诺数的增大而增大,但起伏较大。The hydrodynamic characters of rill flow in the process of rill erosion in purple soil were studied by using runoff simulated experiment under the different slope gradients and the different flow discharges.The results show that the velocity of rill flow on purple soil slope increased according with the increase of runoff,but with the same runoff flux,the velocity of rill flow has no obvious trend.The Reynolds number of rill flow varies between 500 and 4 600 in experiments and it increases quickly with the increase of flow flux on the same slope.The Froude number of rill flow is above 1 in experiments and it belongs to the supercritical flow.The roughness coefficient affected by the slope gradient and flow flux,is closely related to the Reynolds number.It decreases with the increase of Reynolds on gentle slopes,and increases with the increase of Reynolds on steep slope.

关 键 词：紫色土 细沟流 水动力学特征 

分 类 号：S157.1[农业科学—土壤学]