Numerical Study of Flow Downstream a Step with a Cylinder Part 1: Validation of the Numerical Simulations
![Thumbnail](/bitstream/handle/20.500.11850/601519/fluids-08-00055.pdf.jpg?sequence=6&isAllowed=y)
Open access
Datum
2023-02Typ
- Journal Article
Abstract
The backward-facing step flow (BFSF) is a classical problem in fluid mechanics, hydraulic engineering, and environmental hydraulics. The nature of this flow, consisting of separation and reattachment, makes it a problem worthy of investigation. In this study, divided into two parts, the effect of a cylinder placed downstream of the step on the 2D flow structure was investigated. In Part 1, the classical 2D BFSF was validated by using OpenFOAM. The BFSF characteristics (reattachment, recirculation zone, velocity profile, skin friction coefficient, and pressure coefficient) were validated for a step-height Reynolds number in the range from 75 to 9000, covering both laminar and turbulent flow. The numerical results at different Reynolds numbers of laminar flow and four RANS turbulence models (standard k-ε, RNG k-ε, standard k-ω, and SST k-ω) were found to be in good agreement with the literature data. In laminar flow, the average error between the numerical results and experimental data for velocity profiles and reattachment lengths and the skin friction coefficient were lower than 8.1, 18, and 20%, respectively. In turbulent flow, the standard k-ε was the most accurate model in predicting pressure coefficients, skin friction coefficient, and reattachment length with an average error lower than 20.5, 17.5, and 6%, respectively. In Part 2, the effect on the 2D flow structure of a cylinder placed at different horizontal and vertical locations downstream of the step was investigated. Mehr anzeigen
Persistenter Link
https://doi.org/10.3929/ethz-b-000601519Publikationsstatus
publishedExterne Links
Zeitschrift / Serie
FluidsBand
Seiten / Artikelnummer
Verlag
MDPIThema
backward-facing step flow (BFSF); computational fluid dynamics; laminar flow; turbulent flowOrganisationseinheit
03820 - Boes, Robert / Boes, Robert