Numerical Investigation of the Plunging and Vortex-Flow Regimes Occurring in Drop Shafts with a Tangential Intake
Publication: Journal of Irrigation and Drainage Engineering
Volume 148, Issue 8
Abstract
Dropshafts are commonly used as flood discharge structures in urban drainage systems and hydraulic structures. Plunging and vortex flows are the two main flow regimes occurring in the dropshaft with a tangential intake. However, the effects of the intake contraction on the flow regime transition have not been studied. This study aims to present the flow characteristics in the transition process between the plunging and vortex flows in dropshafts, through a series of three-dimensional computational fluid dynamic simulations. With the decrease in the intake contraction ratio, the ratio of rotation and falling velocities along the annular dropshaft wall increases gradually, and the vortex flow can remain a long distance in the vertical dropshaft. The flow regime transition from the plunging flow to the vortex flow is analyzed quantitatively based on two specific velocity ratios of rotation and falling velocities. In addition, for large flow discharges, the effects of intake contraction on the flow rotation performance are more obvious than that for small flow discharges. These findings provide reference for the hydraulic design in dropshaft structures.
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Data Availability Statement
All data that support the findings of this study are available from the corresponding author upon reasonable request. All models used during the study appear in the published article.
Acknowledgments
The reported research was supported by the National Natural Science Foundation of China (Grant No. 51979183) and the Sichuan Science and Technology Program (Grant No. 2020YJ0320).
References
Camino, G. A., D. Z. Zhu, and N. Rajaratnam. 2015. “Flow observations in tall plunging flow dropshafts.” J. Hydraul. Eng. 141 (1): 06014020. https://doi.org/10.1061/(ASCE)HY.1943-7900.0000939.
Chan, S. N., Q. S. Qiao, and J. H. Lee. 2018. “On the three-dimensional flow of a stable tangential vortex intake.” J. Hydro-environ. Res. 21 (Oct): 29–42. https://doi.org/10.1016/j.jher.2018.07.001.
Chen, H. Y., W. L. Xu, J. Deng, Z. P. Niu, S. J. Liu, and W. Wang. 2010. “Theoretical and experimental studies of hydraulic characteristics of discharge tunnel with vortex drop.” J. Hydrodyn. 22 (4): 582–589. https://doi.org/10.1016/S1001-6058(09)60091-3.
Crispino, G., P. Contestabile, D. Vicinanza, and C. Gisonni. 2021. “Energy head dissipation and flow pressures in vortex drop shafts.” Water 13 (2): 165. https://doi.org/10.3390/w13020165.
Crispino, G., D. Dorthe, T. Fuchsmann, C. Gisonni, and M. Pfister. 2016. “Junction chamber at vortex drop shaft: Case study of Cossonay.” In Hydraulic Structures and Water System Management. 6th IAHR Int. Sym. on Hydraulic Structures, edited by B. Crookston and B. Tullis, 437–446. Granada, Spain: Univ. of Granada. https://doi.org/10.15142/T350628160853.
Crispino, G., M. Pfister, and C. Gisonni. 2019. “Hydraulic design aspects for supercritical flow in vortex drop shafts.” Urban Water J. 16 (3): 225–234. https://doi.org/10.1080/1573062X.2019.1648531.
Del Giudice, G., and C. Gisonni. 2011. “Vortex dropshaft retrofitting: Case of Naples city (Italy).” J. Hydraul. Res. 49 (6): 804–808. https://doi.org/10.1080/00221686.2011.622148.
Del Giudice, G., C. Gisonni, and G. Rasulo. 2009. “Vortex drop shaft for supercritical flow.” In Advances in water resources and hydraulic engineering. Berlin: Springer.
Ervine, D. A., and A. A. Ahmed. 1982. “A scaling relationship for a two-dimensional vertical dropshaft.” In Proc., Int. Conf. on Hydraulic Modelling of Civil Engineering Structures, 195–214. Bedford, England: BHRA Fluid Engineering.
Ervine, D. A., and H. T. Falvey. 1987. “Behaviour of turbulent water jets in the atmosphere and in plunge pools.” Proc. Inst. Civ. Eng. 83 (1): 295–314. https://doi.org/10.1680/iicep.1987.353.
Fereshtehpour, M., and M. R. Chamani. 2020. “Flow characteristics of a drop manhole with an internal hanging baffle wall in a storm drainage system: Numerical and experimental modeling.” J. Irrig. Drain. Eng. 146 (8): 04020022. https://doi.org/10.1061/(ASCE)IR.1943-4774.0001490.
Hager, W. H. 2010. Wastewater hydraulics: Theory and practice. Berlin: Springer Science & Business Media.
Hirt, C. W., and B. D. Nichols. 1981. “Volume of fluid (VOF) method for the dynamics of free boundaries.” J. Comput. Phys. 39 (1): 201–225. https://doi.org/10.1016/0021-9991(81)90145-5.
Jain, S. C. 1984. “Tangential vortex-inlet.” J. Hydraul. Eng. 110 (12): 1693–1699. https://doi.org/10.1061/(ASCE)0733-9429(1984)110:12(1693).
Jevdjevich, V., and L. Levin. 1953. “Entrainment of air in flowing water and technical problems connected with it.” In Proc., Minnesota Int. Hydraulic Convention, 439–454. Reston, VA: ASCE.
Liao, L., R. An, J. Li, W. Yi, X. Liu, W. Meng, and L. Zhu. 2019. “Hydraulic characteristics of stepped spillway dropshafts for urban deep tunnel drainage systems: The case study of Chengdu city.” Water Sci. Technol. 80 (8): 1538–1548. https://doi.org/10.2166/wst.2019.405.
Ma, Y., D. Z. Zhu, and N. Rajaratnam. 2016. “Air entrainment in a tall plunging flow dropshaft.” J. Hydraul. Eng. 142 (10): 04016038. https://doi.org/10.1061/(ASCE)HY.1943-7900.0001181.
Ma, Y., D. Z. Zhu, N. Rajaratnam, and B. Duin. 2017. “Energy dissipation in circular drop manholes.” J. Irrig. Drain. Eng. 143 (12): 04017047. https://doi.org/10.1061/(ASCE)IR.1943-4774.0001241.
Pfister, M., G. Crispino, T. Fuchsmann, J. M. Ribi, and C. Gisonni. 2018. “Multiple inflow branches at supercritical-type vortex drop shaft.” J. Hydraul. Eng. 144 (11): 05018008. https://doi.org/10.1061/(ASCE)HY.1943-7900.0001530.
Plant, J., and D. Crawford. 2016. “Pushing the limits of tangential vortex intakes: Is higher capacity and flow measurement possible in a smaller footprint?” In Proc., Water Environment Federation, 4108–4136. Alexandria, VA: Water Environment Federation.
Qi, Y., Y. Wang, and J. Zhang. 2019. “Three-dimensional turbulence numerical simulation of flow in a stepped dropshaft.” Water 11 (1): 30. https://doi.org/10.3390/w11010030.
Rajaratnam, N., A. Mainali, and C. Y. Hsung. 1997. “Observations on flow in vertical dropshafts in urban drainage systems.” J. Environ. Eng. 123 (5): 486–491. https://doi.org/10.1061/(ASCE)0733-9372(1997)123:5(486).
Sallam, K. A., Z. Dai, and G. M. Faeth. 2002. “Liquid breakup at the surface of turbulent round liquid jets in still gases.” Int. J. Multiphase Flow 28 (3): 427–449. https://doi.org/10.1016/S0301-9322(01)00067-2.
Wei, J. F., Y. Y. Ma, D. Z. Zhu, and J. Zhang. 2018. “Experimental study of plunging-flow dropshafts with an internal divider for air circulation.” J. Hydraul. Eng. 144 (9): 06018011. https://doi.org/10.1061/(ASCE)HY.1943-7900.0001510.
Yu, D., and J. H. Lee. 2009. “Hydraulics of tangential vortex intake for urban drainage.” J. Hydraul. Eng. 135 (3): 164–174. https://doi.org/10.1061/(ASCE)0733-9429(2009)135:3(164).
Zhang, W., J. Wang, C. Zhou, Z. Dong, and Z. Zhou. 2018. “Numerical simulation of hydraulic characteristics in a vortex drop shaft.” Water 10 (10): 1393. https://doi.org/10.3390/w10101393.
Zhao, C. H., D. Z. Zhu, S. K. Sun, and Z. P. Liu. 2006. “Experimental study of flow in a vortex drop shaft.” J. Hydraul. Eng. 132 (1): 61–68. https://doi.org/10.1061/(ASCE)0733-9429(2006)132:1(61).
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Journal of Irrigation and Drainage Engineering
Volume 148 • Issue 8 • August 2022
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© 2022 American Society of Civil Engineers.
History
Received: Aug 25, 2021
Accepted: Mar 24, 2022
Published online: Jun 2, 2022
Published in print: Aug 1, 2022
Discussion open until: Nov 2, 2022
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Cited by
- Wangru Wei, Lu Chang, Analytical solutions for vortex flow at the tangential inlet of a vertical dropshaft, Physics of Fluids, 10.1063/5.0135575, 35, 1, (015160), (2023).