Optimizing Structural Design Parameters of Baffle-drop Shaft

YANG Qing-hua; YAO Yuan; YANG Qian; ZHAO Zi-cheng; LIN Hong; MOU Yi; YAO Jin-tao

doi:10.11988/ckyyb.20191127

PDF(9538 KB)

Journal of Changjiang River Scientific Research Institute ›› 2020, Vol. 37 ›› Issue (12) : 72-80. DOI: 10.11988/ckyyb.20191127

HYDRAULICS

Optimizing Structural Design Parameters of Baffle-drop Shaft

YANG Qing-hua¹, YAO Yuan¹, YANG Qian¹, ZHAO Zi-cheng², LIN Hong², MOU Yi³, YAO Jin-tao¹

Author information +

History +

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.

Key words

baffle-drop shaft / model test / numerical simulation / optimization of structural parameters / deep tunnel drainage system

Cite this article

EndNote

Ris (Procite)

Bibtex

Download Citations

YANG Qing-hua, YAO Yuan, YANG Qian, ZHAO Zi-cheng, LIN Hong, MOU Yi, YAO Jin-tao. Optimizing Structural Design Parameters of Baffle-drop Shaft[J]. Journal of Changjiang River Scientific Research Institute. 2020, 37(12): 72-80 https://doi.org/10.11988/ckyyb.20191127

References

[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.