Hydraulic geometry of straight alluvial channels and the principle of least action
Hydraulic geometry of straight alluvial channels and the principle of least action
复制标题
DOI：
10.1080/00221680209499858
复制
发表时间：
2002-03
影响因子：
2.3
通讯作者：
H. Huang;G. Nanson;S. Fagan
中科院分区：
文献类型：
--
作者：
H. Huang;G. Nanson;S. Fagan
天然河流具有规则的水力几何关系，对此尚未给出广泛接受的解释。本文应用最小作用量的物理原理，确定稳定的冲积河道形态。对于稳定的，均匀的冲积河道流，理论推导和案例研究表明，最小的行动时发生的最小势能和MFE（最大流量效率，这里定义为每单位可用水流功率的最大输沙能力）的标准得到满足。天然渠道和那些最有效的或“最少的行动”在这项研究中确定的渠道的平滩水力几何关系之间的一致性表明，冲积渠道通常调整到最有效的部分。最大输沙能力和最小流功率的极值假设的使用提供支持，说明它们基本上是表达式，因此，MFE的更一般的原则，包括。
Natural rivers exhibit regular hydraulic geometry relationships for which no widely accepted explanation has been given. This paper applies the physical principle of least action to the determination of stable alluvial-channel form. For steady, uniform alluvial-channel flow, both theoretical inferences and a case study show that least action occurs when the criteria of minimum potential energy and MFE (Maximum Flow Efficiency, defined here as the maximum sediment transporting capacity per unit available stream power) are satisfied. The consistency between bankfull hydraulic geometry relationships of natural channels and those of maximally efficient or 'least action' channels identified in this study demonstrates that alluvial channels commonly adjust to a maximally efficient section. Support for the use of the extremal hypotheses of maximum sediment transporting capacity and minimum stream power is provided by illustrating that they are essentially expressions of, and hence subsumed by, the more general principle of MFE.