折板型竖井是城市深隧排水系统中一种消能效果明显的水工结构,竖井的结构参数对其泄流量和消能率有重要影响。通过开展物理模型试验和基于Realizable k-ε湍流模型和VOF法的数值模拟,分析不同折板间距和折板倾角的竖井水流流型、最大泄流量、出口流速及消能率。研究结果表明:折板型竖井中基本水流流型有3种,分别为撞壁受限流、临界流和自由跌流;一定范围内增大折板倾角有利于水流流型从撞壁受限流向自由跌流转变,因此,在折板竖井设计中应使折板有适当的角度;竖井的最大泄流量随着折板间距和折板倾角的增大而增大,消能率随泄流量的增大而减小;从竖井的泄流能力和消能效果两方面考虑,当竖井直径为10 m时,折板间距4.85 m,折板倾角为9°～11°的竖井体型为最优。研究成果可为深隧排水系统的设计提供技术支撑。
Abstract
Baffle-drop shaft is an effective energy dissipation structure in urban deep tunnel drainage system. Different structural parameters of the shaft result in large differences in flow capacity and energy dissipation rate. Through experimental study and numerical simulation (using realizable k-ε turbulence model and volume of fluid(VOF) method), the flow pattern, the maximum flow capacity, the outlet flow velocity and the energy dissipation rate of the shaft with different baffle spacings and baffle angles are analyzed. Results demonstrate that the basic flow patterns in the baffle-drop shaft can be summarized into three categories: wall-limited flow, critical flow, and free-fall flow. Increasing the baffle angle is conducive to the transition of flow pattern from wall-limited flow to free-fall flow. Therefore, a proper baffle angle is critical to the design of the shaft. The maximum discharge of the shaft increases as the baffle spacing and baffle angle increase. The energy dissipation rate of the shaft declines with the increase of inflow. Considering both maximum flow capacity and energy dissipation, the shaft performs the best when shaft diameter is 10 m with a baffle spacing of 4.85 m and baffle angles from 9° to 11°. The research finding offers technical support for the design of deep tunnel drainage systems.
关键词
折板型竖井 /
模型试验 /
数值模拟 /
结构参数优化 /
深隧排水系统
Key words
baffle-drop shaft /
model test /
numerical simulation /
optimization of structural parameters /
deep tunnel drainage system
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参考文献
[1] 何贞俊,王 斌,杨 聿,等. 市政排水系统中竖井研究及应用进展[J]. 中国给水排水,2017,33(10):49-53.
[2] RAJARATNAM N,MAINALI A,HSUNG C Y. Observations on Flow in Vertical Dropshafts in Urban Drainage Systems[J]. Journal of Environmental Engineering,1997,123(5):486-491.
[3] CHANSON H. Energy Dissipation and Drop Structures in Ancient Times: the Roman Dropshafts[C]//Proceedings of the Water 99 Joint Congress. Brisbane:Institution of Engineers Australia. Brisbane. June 6-8, 1999:987-992.
[4] GRANATA F,MARINIS G D,GARGANO R,et al. Hydraulics of Circular Drop Manholes[J]. Journal of Irrigation & Drainage Engineering,2011,137(2):102-111.
[5] STEPHENSON D,METCALF J R. Model Studies of Air Entrainment in the Muela Drop Shaft[J]. Proceedings of the Institution of Civil Engineers,1991,91(3):417-434.
[6] CHANSON H. Turbulent Air-water Flows in Hydraulic Structures:Dynamic Similarity and Scale Effects[J]. Environmental Fluid Mechanics,2009,9(2):125-142.
[7] 王 帅. 某高速穿越尾矿库工程的排洪系统试验研究[D]. 石家庄:石家庄铁道大学,2018.
[8] HAGER W H. Vortex Drop Inlet for Supercritical Approaching Flow[J]. Journal of Hydraulic Engineering,1990,116(8):1048-1054.
[9] YU D,LEE J. Hydraulics of Tangential Vortex Intake for Urban Drainage[J]. Journal of Hydraulic Engineering,2009,135(3):164-174.
[10]董兴林,高季章,鲁慎吾,等. 导流洞改为旋涡式竖井溢洪道综合研究[J]. 水力发电,1995,21(3):32-37,60.
[11]董兴林,余闽敏,吴曾谋,等. 导流洞改建旋流式泄洪洞研究与应用[J]. 水力发电,2002,28(4):27-29,71.
[12]牛争鸣,李建中,王永生. 竖井进流水平旋转内消能泄水道的水力特性研究[J]. 应用基础与工程科学学报,1997,5(4):424-432.
[13]牛争鸣,李建中,崔陇天,等. 竖井进流水平旋转内消能泄水道的泄流特性[J]. 西安理工大学学报, 1998,14(1):28-32,66.
[14]ODGAARD A J,LYONS T C,CRAIG A J. Baffle-drop Structure Design Relationships[J]. Journal of Hydraulic Engineering,2013,139(9):995-1002.
[15]王志刚,张 东,张宏伟. 折板消能竖井水力转捩特征研究[J]. 水利水电技术,2015,46(12):44-47,52.
[16]王志刚,张 东,张宏伟,等. 折板消能竖井中的折板功能分析[J].中国水利水电科学研究院学报,2015,13(4):270-276.
[17]王 斌,邓家泉,何贞俊,等. 折板跌落式竖井设计约束条件研究[J].中国水利水电科学研究院学报,2015,13(5):363-367,374.
[18]王 斌,邓家泉,何贞俊,等. 折板竖井结构优化试验研究[C]//第二十七届全国水动力学研讨会文集.北京:海洋出版社,2015:455-461.
[19]MARGEVICIUS A,SCHREIBER A,SWITALSKI R,et al. Baffling Solution to a Complex Problem Involving Sewage Drop Structures [C]//Proceedings of the 33rd IAHR Congress: Water Engineering for a Sustainable Environment. Vancouver, B.C., Canada: Proceedings of the Water Environment Federation. Vancouver, Canada. August 9-14, 2009: 1-9.
基金
国家自然科学基金项目(51478403);中铁二院工程集团有限责任公司科研项目(KYY2019050(19-22))
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