İç İçe Borulu Yay Tip Türbülatörlü Bir Isı Değiştiricisinin RNG k-ε Türbülans Modeli ile Sayısal Analizi

Yıl 2020, Cilt: 8 Sayı: 1, 64 - 78, 23.03.2020

Haci Mehmet Şahin , Ali Riza Dal , Medine Özkaya

https://doi.org/10.29109/gujsc.625585

Cited By: 5

Öz

Bu çalışmada, eşmerkezli iç içe borulu bir ısı değiştiricisinin boyutlarının
azaltılması ile ısı transferinin iyileştirilmesi ve sürtünme özelliklerinin
belirlenmesi amacıyla yay tipi türbülatör kullanarak, RNG k-ε modeli ile
sayısal analizler yapılmıştır. Çalışmalar Reynolds (Re) sayısının 3000 ila 18000 aralığında yapılmıştır. Sonlu Hacimler
Metoduna dayalı ANSYS-fluent adlı bir Hesaplamalı Akışkanlar Dinamiği (HAD)
kodu ile sayısal simülasyonlar yapılmıştır. Sayısal analizlerde, Model ➀ (RNG-Standard wall function), Model ➁ (RNG-Non-Equilibrium wall
function) ve Model ➂ (RNG-Enhanced wall
treatment) üç temel türbülans modelleri kullanılmıştır. Bu nedenle, deneysel ve
sayısal analizlerle RNG k-ε modelinin üç temel türbülans modelleri arasında
karşılaştırma yapılarak, en iyi sonucu Model
➀ türbülans modeli vermiştir.

Anahtar Kelimeler

Türbülatör, HAD Analiz, RNG k-ε, Isı Değiştiricileri

Numerical Analisis by RNG k-ε Turbulent Model of a Concentric Tube Heat Exchanger with Coiled Wire Turbulator

Öz

In this study, a concentric
tube heat exchanger with coiled wire turbulators were analysised numerically by
RNG k-ε Turbulent Model in order to be reduced heat exchanger sizes, increased
heat transfer enhancement and to be obtained friction characteristics. The
analyses were done in a range of Reynolds (Re)
number from 3000 to 18000. The numerical simulations were done by using a CFD
code namely ANSYS fluent, using finite volume method. Three main turbulence
models of RNG k-ε were employed in the simulations such as Model ➀ (RNG-Standard wall function), Model
➁ (RNG-Non-Equilibrium wall
function) and Model ➂ (RNG-Enhanced wall treatment). Therefore,
the numerical analyses carried out to compare with the experimental results in
order to determine the best fitting model using each three main turbulence
models of RNG k-ε model, Model ➀ has given
the best result.

Anahtar Kelimeler

Turbulator, CFD analysis, RNG k-ε, Heat Exchangers

Kaynakça

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