《水文学杂志》刊登“地形对明渠流分叉中流量分布的影响研究”

作者：Emmanuel Mignot , Cheng Zeng, Gaston Dominguez, Chi-Wai Li, Nicolas Rivière, Pierre-Henri Bazin

期刊：《水文学杂志》，2013年6月28日，494期，10-19页

关键字：亚明渠流；支流；阻碍；实验性；数值；城市街道洪水

摘要：过去研究模拟城市洪水时，大多数方法需要简化城市的地形，并且不考虑街道上的障碍物，例如公交车车站，树木和停放的汽车。本文的目的是探讨针对一个简单的三分叉结构路口，由于忽略了路口处障碍物等地形奇异点所造成的误差，特别是模拟下游街道间流量分配的误差。本研究利用电磁流量计对总共14个试验水流进行了观测，每个水流中被依次放入了9个障碍物，每个障碍物占过流截面的六分之一。同时利用水平PIV观测每个给定试验水流的速度场，并且所有水流均采用流体力学方法计算。结果表明，流量分配的变化与造成水流分岔口的障碍物的位置和水流分离界面的位置有密切的联系，并且入流的弗劳德数的影响非常显著。但是正常水深对流量分配的影响不大。终上所述，即使对高弗劳德数的水流，因障碍物引起的流量分配的变化仍低于入流流量的15%。

Impact of topographic obstacles on the discharge distribution in open-channel bifurcations

Authors: Emmanuel Mignot , Cheng Zeng, Gaston Dominguez, Chi-Wai Li, Nicolas Rivière, Pierre-Henri Bazin

Journal: Journal of Hydrology,Volume 494, 28 June 2013, Pages 10–19

Keywords: Subcritical open-channel flows; Bifurcation; Obstacles; Experimental; Numerical; Flooded urban streets

Abstract: When simulating urban floods, most approaches have to simplify the topography of the city and cannot afford to include the obstacles located in the streets such as bus stops, trees and parked cars. The aim of the present paper is to investigate the error made when neglecting such singularities in a simple flooded 3-branch crossroad configuration with a specific concern regarding the error in discharge distribution to the downstream streets. Experimentally, the discharge distribution for 14 flows in which nine obstacles occupying 1/6 of the flow section are introduced one after the other is measured using electromagnetic flow-meters. The velocity field for one given flow is obtained using horizontal-PIV. Additionally, all these flows are computed using a CFD methodology. It appears that the modification in discharge distribution is mostly related to the location of the obstacles with regards to the intersection, the location of the separating interface and is strongly impacted by the Froude number of the inflow while the influence of the normalized water depth remains very limited. Overall, the change in discharge distribution induced by the obstacles remains lower than 15% of the inflow discharge even for high Froude number flows.

文献来源：http://www.sciencedirect.com/science/article/pii/S002216941300317X