摘要
坡面水蚀动力与侵蚀产沙关系是水蚀预报的关键问题之一.本文通过光滑水槽试验和模拟冲刷试验,对坡面水流动力学特性(径流流速、剪切力以及能耗)及其与侵蚀产沙关系进行了系统研究.结果表明,坡面薄层水流呈滚波流特征,坡面流流速沿程变化呈波动趋势,随流量和坡度的增加而增大;坡面单宽径流剪切力、单宽径流能耗和坡面径流单宽输沙率随流量的增加而增加,随坡度呈抛物线趋势变化,说明坡面土壤侵蚀过程存在临界坡度,在本试验条件下,临界坡度位于21—24°之间.坡面单宽径流输沙率和单宽径流剪切力、单宽径流能耗之间均存在良好的线性关系.
Relation between water erosion dynamics and sediment yield is one of the key problem in soil erosion prediction.In this study,flow dynamics（inculding flow velocity,shear stress and energy consumption） were studied by runoff scouing on smooth flume and soil flume.Results indicated that sheet flow on smooth slope moved in roll waves,flow velocity fluctuated along the flume,and increased with runoff discharge and slope gradient.Runoff shear stress,runoff energy consumption and sediment transportation of unit width runoff increased with runoff discharge,and changed in parabola shape with slope gradient,which indicated the existance of critical slope gredient.In this experiment,critical slope gredient was between 21—24°.Further analysis showed that linear relation existed between sediment transportation and runoff shear stress,runoff energy consumption of unit width runoff.
出处
《应用基础与工程科学学报》
EI
CSCD
2010年第3期435-441,共7页
Journal of Basic Science and Engineering
基金
"国家重点基础研究发展计划项目(2007CB407206)"
国家科技支撑项目(2006BAD09B02)
关键词
陡坡
水动力
能耗
水力侵蚀产沙
临界坡度
steep slope
flow dynamic characters
runoff energy consumption
water erosion and sediment yield
critical slope gradient
