International Research Journal of Innovations in Engineering and Technology - IRJIET International Open Access, Monthly, Peer Reviewed, Reputed Journal ISSN (online): 2581-3048

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DOI Prefix: 10.47001/IRJIET

Simulation Investigation of Flows over an Inclined Backward-Facing Step

Abstract

This study deals with the flow investigation of a backward-facing incline step using the RANS turbulence model (STD k-ε and SST k-ω) with angle 50, 100 and 150. The Reynolds numbers used are 17,500 and 30,000.  The motivation for this research stems from the fact that in aerodynamics analysing, the flow over an inclined step will enable us in understanding the features of the rear wake. A great amount of the energy necessary to propel the airfoil gets dissipated by vortex shedding generated in the rear, so it is of paramount importance to understand the properties of the wake. In this paper, the flow over a backward step is analysed and the results are compared with existing scholarly literature for validation. Attention was paid specifically to the separation region behind the step and the shear layer relaxation after the reattachment in the downstream part of the channel. The influence of Reynolds number, expansion ratio and turbulence intensity on flow separation and reattachment was investigated and obtained for various step angles using the STD k-ε and SST k-ω model and it was observed that the SST k-ω predict recirculation better than the STD k-ε model with about 0.1percent. In conclusion, the upstream boundary layer plays a decisive role in flow separation and reattachment.

Country : Indonesia

1 Casimir Uchenna Agbakaja2 Berkah Fajar Tamtomo Kiono3 Khoiri Rozi

  1. Department of Mechanical Engineering, Diponegoro University, Jl. Prof. Sudharto, SH, Semarang 50275, Indonesia
  2. Department of Mechanical Engineering, Diponegoro University, Jl. Prof. Sudharto, SH, Semarang 50275, Indonesia
  3. Department of Mechanical Engineering, Diponegoro University, Jl. Prof. Sudharto, SH, Semarang 50275, Indonesia

IRJIET, Volume 7, Issue 7, July 2023 pp. 1-11

doi.org/10.47001/IRJIET/2023.707001

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