Art Arda Yerleştirilmiş Eş Sıcaklıktaki İki Silindir Etrafında Akış ve Isı Geçişi

Year 2020, , 342 - 353, 28.06.2020

Zerrin Sert , Çisil Timuralp

https://doi.org/10.35193/bseufbd.711597

Abstract

Bu çalışmada, ard ard yerleştirilen eş sıcaklıktaki iki silindir etrafındaki akış ve ısı geçişi geçici rejimde sayısal olarak incelenmiştir. İki boyutlu, geçici rejimde süreklilik, momentum ve enerji denklemleri Fluent yazılımı kullanılarak çözdürülmüştür. Çalışma akışkanı olarak hava (Pr=0.7) ve su (Pr=7) seçilmiştir. Reynolds sayısı 100, 150 ve 200 olarak alınmıştır. Ayrıca silindir merkezleri arasındaki uzaklık, L/D=1.5 ve 5 olarak seçilmiştir. Her durum için elde edilen sürükleme katsayısı, kaldırma katsayısı ve Nusselt sayısı gibi akış ve ısı transfer parametreleri, literatürdeki mevcut çalışmalarla karşılaştırılmıştır. L/D=1.5 olduğunda iki silindir arasında girdaplar oluşmazken, L/D=5 durumunda iki silindir arasında girdapların oluştuğu görülmektedir. Ayrıca Reynolds sayısının artması ile aşağı akış bölgesinde vorteksler ikinci silindire daha yakın bir mesafede oluşmuştur.

Keywords

Art arda silindirler, Geçici rejim, Isı geçişi, Zorlanmış taşınım

Numerical Investigation of Heat Transfer and Fluid Flow Around Two Tandem Cylinders

Abstract

In this study, the unsteady flow and heat transfer from two tandem cylinders are studied numerically. For two-dimensional transient state continuity, Navier-Stokes and energy equations are solved using Fluent® software. The working fluids are considered as air (Pr=0.7) and water (Pr=7). The simulations are performed for Reynolds numbers of 100, 150 and 200. The distance between the cylinders is also taken as L/D=1.5 and L/D=5. The flow and heat transfer characteristics such as drag coefficient, lift coefficient and Nusselt number obtained for each case are compared with the studies in the literature. For L/D=5, the vortex shedding observed between the cylinders while no vortex is observed for L/D=1.5. With an increase in the Reynolds number, vortices are formed closer to the second cylinder in the downstream region.

Keywords

Tandem cylinders, Transient state, Heat transfer, Force convection

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