Numerical Analysis of Turbulent Flow over a Backward-facing Step in an Open Channel

• Autorzy: Saleem Bala Kawa M. , Mustafa Andam , Kareem Dalshad Ahmed , Yuce Mehmet Ishak , Szydłowski Micchał , Al-Ansari Nadhir

Identyfikatory

DOI

10.2478/heem-2023-0004

• Języki publikacji: EN

Abstrakty

EN

Computational examinations of the flow field in an open channel having a single Backward- -Facing Step (BFS) with a constant water depth of 1.5 m were performed. The effects of the expansion ratio, and the flow velocity along the reattachment length, were investigated by employing two different expansion ratios of 1.5 and 2, and eight various flow velocities of 0.5, 1, 2, 3, 4, 5, 7.5 and 10 m/sec in the Computational Fluid Dynamic (CFD) simulations. Commercially available CFD software, ANSYS FLUENT, was used for calculations. The simulation outcomes were verified using experimental results. Moreover, analyses were performed by using two equation turbulence closure models, K-ε family (standard, RNG and realizable), and K-ω family (Wilcox’s and SST K-ω). The analyses have revealed that the reattachment length increases with an increase in the expansion ratio, the flow velocity and the Reynolds number. The results obtained for two expansion rates and eight different flow velocities have shown insignificant differences between one turbulence closure model and the others. Furthermore, it was observed that both velocity and expansion ratios have an effect on the reattachment zone size.

Słowa kluczowe

EN

open channel; backward-facing step; reattachment length; expansion ratio; Kɛ- model; Kω- model

• Wydawca: Institute of Hydro-Engineering of Polish Academy of Sciences
• Czasopismo: Archives of Hydro-Engineering and Environmental Mechanics
• Rocznik: 2023
• Tom: Vol. 70, nr 1
• Strony: 49--69
• Opis fizyczny: Bibliogr. 40 poz., rys., tab., wykr.

Twórcy

autor

Saleem Bala Kawa M.

• General Directorate of Water and Sewage, Ministry of Municipalities and Tourism, Erbil 44001, Iraq

autor

Mustafa Andam

• Faculty of Civil and Environmental Engineering, Gdansk University of Technology, Narutowicza 11/12, Gdansk 80–233, Poland

autor

Kareem Dalshad Ahmed

• Erbil Technology College, Erbil Polytechnic University, Erbil 44001, Iraq

autor

Yuce Mehmet Ishak

• Department of Civil Engineering, Gaziantep University, Gaziantep 27310, Turkey

autor

Szydłowski Micchał

• Faculty of Civil and Environmental Engineering, Gdansk University of Technology, Narutowicza 11/12, Gdansk 80–233, Poland

autor

Al-Ansari Nadhir

• Department of Civil, Environmental and Natural Resources Engineering, Lulea University of Technology, Lulea 971 87, Sweden

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