摘要
根据人工模拟降雨试验,研究了黄土丘陵沟壑区坡面侵蚀水动力过程。结果表明:薄层水流的流速~流量、阻力系数~雷诺数及弗罗德数~雷诺数等3种关系均呈幂函数形式,除阻力系数~雷诺数关系递减外,其余均呈递增。降雨所形成的坡面流属过渡流和紊流,坡面流在时空分布上是非稳定和非均匀的,是在下垫面和降雨影响下严重受扰的扰动流,且具有急流的特点。薄层水流的这种流态特征是侵蚀形成的动力原因。分析了径流量与坡度、雨强,产沙量与坡度、雨强及径流量之间的关系,对深入揭示坡面侵蚀产沙规律有重要的意义。
The dynamic mechanism of slop runoff in soil erosion chain of loess hilly region is experimentally studied by means of rainfall simulation.The result shows that:1\^the relationships of current velocity~flow discharge,flow resistance coefficient~Reynolds number and Froude number~Reynolds number can be described by power function;2\^the runoff flow is not a typical laminar flow but a turbulent flow or transition flow distributed unsteadily and unevenly in temporal and space.Slope runoff possesses the feature of torrential flow disturbed by heavily underlying surface and rainfall.It is the fundamental cause of erosion.
出处
《水利学报》
EI
CSCD
北大核心
2003年第9期66-70,共5页
Journal of Hydraulic Engineering
基金
中国科学院知识创新工程项目(KZCX1 10 04)
国家自然科学基金(49671052)
黄土高原土壤侵蚀与旱地农业国家重点实验室(10501 78)联合资助
关键词
黄土丘陵区
薄层水流
土壤侵蚀
水力参数
动力机制
loess hilly region
sheet flow
soil erosion
hydraulic parameter
dynamic mechanism