《Journal of Hydraulic Engineering》刊登“二维溃坝水流的试验与数值研究”

作者：LaRocque, Lindsey Ann；Imran, Jasim；Chaudhry, M. Hanif

刊物：《Journal of Hydraulic Engineering》，2013年6月，第139卷第6期，569-579页

关键词：溃坝；大坝破坏；数值模拟；模拟；超声波速分析器；速度分布图；流体体积

摘要：本文介绍了从理想的溃坝试验和试验的数值模拟结果中获得流速分布图的方法。实验室中的溃坝水流通过突然开启三个不同上游水头的水道闸门来获得的，试验前下游水道模拟河床的干燥条件。超声多普勒速度分析器用于记录闸门被移动后上下游八个不同位置的瞬时速度分布。这些试验提供了短期内不稳定水流的时空变化数据。二维试验利用计算流体动力学求解方法来进行模拟。通过观察得到下列现象：（1）紊流模型不影响上游水库的速度分布，但是对下游流速的预测有很大影响。（2）特定位置的速度大小随时间变化，但是速度分布图的形状保持相似；(3)倾斜河床上的平顺溃坝水流数值解和大涡流的数值模拟结果与实际测量的水流表面分布图流速分布基本一致；（4）不同水库水头和特定水头的不同位置得到的流速分布图的无量纲化结果揭示出这些剖面的剪切层厚度大约是初始水库水头的5%；（5）大涡流模型的模拟结果与紊流模拟结果较为一致；因此，LES模型对于准确预测溃坝水流是可行的。

Experimental and Numerical Investigations of Two-Dimensional Dam-Break Flows

Authors：LaRocque, Lindsey Ann；Imran, Jasim；Chaudhry, M. Hanif

Journal：Journal of Hydraulic Engineering. Jun2013, Vol. 139 Issue 6, p569-579

Key Word：Dam break；Dam failures；Numerical simulation；Simulation；Ultrasonic velocity profiler；Velocity profile；Volume of fluid (VOF)

Abstract：This paper presents measurements of velocity profiles obtained from idealized dam-break experiments and results from numerical simulations of these experiments. Dam-break flows were generated in the laboratory by suddenly lifting a gate inside a flume for three different upstream heads with a dry-bed downstream condition. Ultrasonic Doppler velocity profilers were used for recording transient velocity profiles at eight different locations upstream and downstream of the removed gate. These experiments provided data on the spatio-temporal evolution of the flow field in an unsteady flow of relatively short duration. The two-dimensional experiments were simulated using a computational fluid dynamics solver. The following observations are made: (1) turbulence modeling does not affect the velocity profile in the upstream reservoir, but has significant influence on the prediction of downstream velocity; (2) the velocity magnitude at a specific location changes with time, but the shape of the velocity profiles remains similar; (3) an analytical solution for frictionless dam-break flow on a sloping bed and numerical simulation with the large eddy simulation (LES) modeling show satisfactory agreement with measured water surface profile; (4) nondimensionalization of reservoir-side velocity profiles resulting from different reservoir heads and at different locations from a specific head reveals that the shear layer thickness of these profiles is approximately 5% of the initial reservoir head; (5) measurement and simulation with the LES model for turbulence show satisfactory agreement, suggesting that the LES modeling is a viable approach for an accurate prediction of dam-break flows.

原文链接：https://vpn2.nlc.gov.cn/prx/000/http/web.ebscohost.com/ehost/detail?vid=5&sid=ac043b4f-a1de-4aa4-84bc-46bb6fdf2013%40sessionmgr114&hid=124&bdata=Jmxhbmc9emgtY24mc2l0ZT1laG9zdC1saXZl#db=a9h&AN=87479190