坡面流阻力研究进展

坡面流阻力的研究对了解坡面流水流特性、汇流过程、土壤侵蚀和坡面产沙机理都非常重要。本文分5个方面总结了坡面流阻力研究的最新进展:(1)坡面流阻力系数与雷诺数的关系;(2)光滑床面上的坡面水流阻力;(3)粗糙床面上的坡面水流阻力;(4)降雨对坡面流阻力影响的研究;(5)坡面流阻力的计算模型。综合前人研究发现,阻力系数与雷诺数在不同的条件下呈正相关或负相关关系;用叠加法计算不同条件下的坡面流阻力有其合理的一面,也有不足之处;粗糙动床条件下的坡面水流阻力计算模型更接近实际情况。最后,本文指出了当前坡面流阻力研究存在的主要问题和未来需要突破的主攻方向。

Recent progress in studies of overland flow resistance

Overland flow resistance(OFR) is an important parameter which reflects overland flow characteristics.Exploring OFR is critical for understanding the flow characteristics,overland flow routing,soil erosion and mechanism of sediment yield on sloping land.This paper summarizes the five aspects of recent progress in studies of overland flow resistance:(1) the relationship between overland flow resistance and Reynolds number;(2) flow resistance of plane beds;(3) flow resistance of rough beds;(4) the influence of rainfall on OFR,and(5) flow resistance modeling.It is found that(1) the relation between overland flow and Reynolds number can be a positive or negative correlation under different conditions;(2) linear superposition approach to calculate the overland flow resistance under different conditions is problematic;(3) overland flow resistance calculation model is close to the practical condition on rough mobile beds.At last,this paper points out the major problems in current studies of overland flow resistance and the hot topics in this field.