水科学进展2018，Vol.29Issue(2)：179-185,7.DOI:10.14042/j.cnki.32.1309.2018.02.004
冲积河流泥沙输移幂律函数指数变化规律
Exponent change rule of power law for sediment transport in alluvial rivers
摘要
Abstract
The empirical power law relationship model and non-equilibrium sediment transport theory are two different methods used to describe the suspended sediment transport in alluvial rivers.The mathematical comparison results show that,for steady uniform flow,the derivatives of sediment concentration of the two above mentioned methods are first order approximate when sediment transport state is near equilibrium condition,and the variation of the saturation recovery coefficient is considered in power law relationship when sediment transport state is far away from the equilibrium condition.Based on the equivalence property,the calculation formula of exponent in power law function is established,showing that the value of exponent varies with the saturation recovery coefficient,sediment fall velocity,unit width discharge and longitudinal distance.Based on the derivative of power law function for the structural features of sediment concentration,the calculation expression of saturation recovery coefficient which is far away from the equilibrium condition is extracted and expressed.Finally,a new power law relationship model with changing exponent is proposed and applied to the sand basin.The application result revealed that the computed suspended sediment concentration along the distance of the sand basin is in suitable agreement with the measured values.关键词
冲积河流/泥沙输移/不平衡输沙/幂律函数/变幂指数Key words
alluvial rivers/sediment transport/non-equilibrium sediment transport/power law/changing exponent分类
建筑与水利引用本文复制引用
申红彬,吴保生..冲积河流泥沙输移幂律函数指数变化规律[J].水科学进展,2018,29(2):179-185,7.基金项目
国家重点基础研究发展计划(973计划)资助项目(2011CB403304)The study is financially supported by the National Basic Research Program of China (No.2011CB403304). （973计划）
