Geriye dönük basamaklı kanalda eğimli elastik kanadın ısı transferine etkisi

Yıl 2026, Cilt: 46 Sayı: 1 , 66 - 78 , 01.05.2026

Boualem Ikram , Noureddine Bouhamri , Mohamed Bouzit , Mohamed Bouhafs , Ikram Djellid

https://doi.org/10.47480/isibted.1750373

https://izlik.org/JA33UB62JM

Öz

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.

Anahtar Kelimeler

Geri adımlı basamak (BFS) , Isı transferi , Akışkan-yapı etkileşimi (FSI) , Esnek kanat , Zorlanmış taşınım

Effect of an Inclined Elastic Fin on Heat Transfer in a Backward-Facing Step Channel

https://izlik.org/JA33UB62JM

Öz

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.

Anahtar Kelimeler

Backward- facing step (BFS) , Heat transfer , Fluid-structure interaction (FSI) , Flexible fin , Forced convection

Kaynakça

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