Three-Dimensional Turbulence Numerical Simulation of Flow in a Stepped Dropshaft
1
State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China
2
Department of Foundation Studies, Xinjiang Institute of Engineering, Urumqi 830023, China
*
Authors to whom correspondence should be addressed.
Water 2019, 11(1), 30; https://doi.org/10.3390/w11010030
Received: 18 November 2018 / Revised: 17 December 2018 / Accepted: 17 December 2018 / Published: 24 December 2018
(This article belongs to the Special Issue Advances in Hydraulics and Hydroinformatics)
Abstract
The dropshaft structure is usually applied in an urban drainage system to connect the shallow pipe network and the deep tunnel. By using the renormalization group (RNG) k~ε turbulence model with a volume of fluid method, the flow pattern and the maximum relative water depth over a stepped dropshaft with a different central angle of step were numerically investigated. The calculated results suggested that the flow in the stepped dropshaft was highly turbulent and characterized by deflection during the jet caused by the curvature of the sidewall. According to the pressure distribution on the horizontal step and the flow pattern above the step, the flow field was partitioned into the recirculating region, the wall-impinging region and the mixing region. In addition, with the increase in the central angle of step, the scope of the wall-impinging region and the mixing region increased and the scope of the recirculating region remained nearly unchanged. The maximum water depth increased with the increase in discharge. In the present work we have shown that, as the value of the central angle of step increased, the maximum water depth decreased initially and increased subsequently. View Full-Text
Figure 1
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MDPI and ACS Style
Qi, Y.; Wang, Y.; Zhang, J. Three-Dimensional Turbulence Numerical Simulation of Flow in a Stepped Dropshaft. Water 2019, 11, 30.
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