水科学进展2012，Vol.23Issue(2)：229-235,7.
模拟降雨条件下坡面流水动力学特性研究
Experimental study of shallow flow hydraulics on a hillslope under artificial rainfall conditions
摘要
Abstract
In order to understand the hydrodynamic characteristics of overland flow on hillslopes, based on the theories in fluid mechanics and sediment transport mechanics, variations in hydraulic parameters of overland flow are studied experimentally for 5 artificial rainfall intensities and 5 slope gradients. The results show that the Reynolds numbers of shallow flow are found to be less than 580 under all 5 artificial rainfall conditions, and the corresponding flow regimes are all unstable laminar flow. The flow type varies with the rainfall intensities and the slope gradients. For gentle slopes and low rainfall intensities, the bed forms are at the low-energy condition and in the transition state. Sand ripples appear on the bed surface and the flow is sub-critical in general. In contrast, for steep slopes and high rainfall intensities, the transition from sand ripples to sand dunes occurs on the bed surface and the flow is supercritical in general. A formula is derived to estimate the shallow flow resistance and tested using the experimental data. The result shows that the formula gives negligible error in resistance calculations. The formula can thus be used as a reference to the establishment of prediction models for the soil erosion simulation on hillslopes.关键词
模拟降雨/坡面/薄层水流/水力学特性Key words
simulated rainfall/ slope/ shallow flow/ hydraulic characteristic分类
农业科技引用本文复制引用
张宽地,王光谦,吕宏兴,王占礼,刘俊娥..模拟降雨条件下坡面流水动力学特性研究[J].水科学进展,2012,23(2):229-235,7.基金项目
国家自然科学基金资助项目(41001159) （41001159）
陕西省自然科学基金资助项目(2011JQ5004) （2011JQ5004）
