Isı Bilimi ve Tekniği Dergisi 1300-3615 2667-7725 Türk Isı Bilimi ve Tekniği Derneği 10.47480/isibted.1750373 Fluid Mechanics and Thermal Engineering (Other) Akışkan Mekaniği ve Termal Mühendislik (Diğer) Geriye dönük basamaklı kanalda eğimli elastik kanadın ısı transferine etkisi Effect of an Inclined Elastic Fin on Heat Transfer in a Backward-Facing Step Channel https://orcid.org/0009-0006-3075-5377 Ikram Boualem University of Science and Technology of Oran, Mohamed Boudiaf https://orcid.org/0000-0002-9806-7865 Bouhamri Noureddine University of Oran 2 Mohamed Ben Ahmed https://orcid.org/0000-0002-1417-7291 Bouzit Mohamed University of Science and Technology of Oran, Mohamed Boudiaf https://orcid.org/0000-0002-8911-7015 Bouhafs Mohamed University of Oran 2 Mohamed Ben Ahmed https://orcid.org/0009-0001-2249-1010 Djellid Ikram University of Oran 2 Mohamed Ben Ahmed 05 01 2026 46 1 66 78 07 25 2025 10 26 2025 Copyright © 1977, Isı Bilimi ve Tekniği Dergisi 1977 Isı Bilimi ve Tekniği Dergisi

Bu çalışma, Sonlu Elemanlar Yöntemine (FEM) dayalı sayısal simülasyon yoluyla, eğimli esnek bir kanat kullanarak geri adımlı basamak konfigürasyonunda ısı transferi iyileştirmesini araştırmaktadır. Esnek kanadın konumunun, zorlanmış taşınım havası akışkan olarak kullanılarak, termal ve akışkan dinamik performans üzerindeki etkisi araştırılmaktadır. Isı transferi karakteristikleri, kanalda üç farklı konumda (P1, P2, P3) Reynolds sayısı (Re 50 ile 200 arasında), Cauchy sayısı (Ca 10⁻⁸ ile 10⁻⁴ arasında) ve sabit Prandtl sayısı Pr=0.71 için incelenmiştir. Sonuçlar, ısı transferinde bir iyileşme göstermekte olup, en iyi performansın Re=200 ve Ca=10⁻⁸ (daha esnek kanat) değerlerinde elde edildiği görülmektedir. Özellikle kanadın basamağa daha yakın konumlandırıldığı durumda, kanatsız duruma kıyasla Nusselt sayısında %40’lık kayda değer bir artış gözlemlenmiştir. Ayrıca, makale, akış ayrılması ve geri dönme bölgelerinin esnek kanat yapısıyla etkileşiminin taşınımla ısı transferine etkisini göstermektedir. Bu bulgular, kompakt termal sistemlerde pasif ısı transferi iyileştirmesi için esnek kanatların etkili bir strateji olma potansiyelini vurgulamaktadır.

The current study investigates heat transfer improvement in backward-facing step configuration using a inclined flexible fin through numerical simulation based on the Finite Element Method (FEM). Investigating the influence of the position of the flexible fin, on thermal and fluid dynamic performance using forced convection air as fluid. The heat transfer characteristics are studied for different Reynolds numbers (Re between 50 and 200), Cauchy numbers (Ca from10-8, to 10-4) at three positions (P1, P2, P3) in the channel, and a constant Prandtl number of Pr=0.71. The results show an enhancement in heat transfer, with best performance occurring at a Reynolds number of 200 and a Cauchy number of Ca=10-8 (more flexible fin). Specifically, when the fin located closer the step, a remarkable 40% increase in the Nusselt number was observed compared to the case of without fin. Also, the paper shows the influence of flow separation and recirculation zones interaction with the elastic character of the fin on affecting convective heat transfer. These findings highlight the potential of elastic fins as an effective strategy for passive heat transfer enhancement in compact thermal systems.

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