Investigation of a Flexible V-Fin for Heat Transfer Enhancement in a Backward-Facing Step

Document Type : Full Length Research Article

Authors

1 Institute of Industrial Maintenance and Safety, University of Oran 2 Mohamed Ben Ahmed, Laboratory of Production Engineering and Industrial Maintenance (LGPMI), B.P. 170 El M’naouer Oran 31000, Algeria

2 Faculty of Mechanical Engineering, University of Science and Technology of Oran Mohamed Boudiaf, El M’naouer, Laboratory of Maritime Sciences and Engineering (LSIM), B.P.1505, 31000, Oran, Algeria

Abstract

A numerical study was conducted to enhance heat transfer in a backward-facing step configuration via forced convection. Using the finite element method, simulations were performed for Reynolds numbers from 50 to 200. A flexible V-fin was introduced to direct the coolant (air) flow toward the heated wall. The fin's vertical position (y = 0, H/10, H/5) and elasticity, governed by the Cauchy number (Ca = 10⁻⁴, 10⁻⁵, 10⁻⁶, 10⁻⁷), were key variables. The optimal configuration (y = H/5, Ca = 10⁻⁷, Re = 200) yielded a 30.75% increase in the average Nusselt number over the baseline without a fin. The results confirm that the fin consistently improves thermal performance, whether rigid or flexible. This study employs finite element simulations to analyze forced convection heat transfer in a backward-facing step channel. The research investigates the effect of a flexible V-fin. compared to the case without a fin. Crucially, the fin's presence improved heat transfer performance regardless of its rigidity.

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Main Subjects

References

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Journal of Heat and Mass Transfer Research
Volume 13, Issue 3 - Serial Number 27
In Progress
September 2026
Pages 295-313

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History

  • Receive Date: 20 August 2025
  • Revise Date: 06 November 2025
  • Accept Date: 29 November 2025

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