<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>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 e ects of the expansion ratio, and the flow velocity along the reattachment length, were investigated by employing two di erent 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-ɛ 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 di erent flow velocities have shown insignificant di erences between one turbulence closure model and the others. Furthermore, it was observed that both velocity and expansion ratios have an e ect on the reattachment zone size.</p>
</abstract>

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 e ects of the expansion ratio, and the flow velocity along the reattachment length, were investigated by employing two di erent 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-ɛ 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 di erent flow velocities have shown insignificant di erences between one turbulence closure model and the others. Furthermore, it was observed that both velocity and expansion ratios have an e ect on the reattachment zone size.

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

Department of Civil, Environmental and Natural Resources Engineering

Archives of Hydro-Engineering and Environmental Mechanics

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

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...

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

Publicado en línea: 15 may 2023

Páginas: 49 - 69

Recibido: 01 dic 2022

DOI: https://doi.org/10.2478/heem-2023-0004

Palabras clave
open channel, backward-facing step, reattachment length, expansion ratio, K- model, K- model

© 2023 Bala Kawa M. Saleem et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

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

Publicado en línea: 15 may 2023

Páginas: 49 - 69

Recibido: 01 dic 2022

DOI: https://doi.org/10.2478/heem-2023-0004

Palabras claveopen channel, backward-facing step, reattachment length, expansion ratio, K- model, K- model

© 2023 Bala Kawa M. Saleem et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Palabras clave
open channel, backward-facing step, reattachment length, expansion ratio, K- model, K- model