Nanoparticle Shape Effect on Natural Convection in a Corner Partitioned Square Cavity

Yıl 2016, Cilt: 31 Sayı: ÖS2, 143 - 152, 15.10.2016

Fatih Selimefendigil , Aslı Akyol İnada

https://doi.org/10.21605/cukurovaummfd.316738

Öz

In this study, numerical investigation of natural convection in a corner partitioned square cavity filled with nanoparticles of different shapes was performed by using finite element method. The left and right vertical walls of the cavity are kept at constant temperatures while the horizontal walls are adiabatic and the corner partition is conductive. The numerical study was performed for various values of Rayleigh numbers, solid nanoparticle volume fractions, radii of the corner partition and different nanoparticle shapes. It was observed that average heat transfer enhances as the value of the Rayleigh number, nanoparticle volume fraction and size of the conductive partition increases. Cylindrical shape nanoparticles show the best performance and spherical ones show the worst performance in terms of heat transfer enhancement.

Anahtar Kelimeler

Conjugate natural convection, Nanofluids, Corner partition, Finite element method

Köşe Bölmeli Kare Muhafazada Nanopartikül Şekil Etkisinin Doğal Konveksiyon Üzerine Etkileri

Öz

Bu çalışmada, farklı şekillerde nanopartiküller ile doldurulmuş köşe bölmeli kare boşlukta doğal konveksiyonun sayısal incelenmesi sonlu elemanlar yöntemi kullanılarak gerçekleştirilmiştir. Boşluğun sol ve sağ dikey duvarları sabit sıcaklıkta tutulurken, yatay duvarlar adyabatik ve köşe bölmesi iletkentir. Sayısal çalışma farklı nanopartikül şekilleri ve köşe bölmesinin yarıçapı, katı nanopartikül hacim kesirleri, Rayleigh sayılarının çeşitli değerleri için uygulanmıştır. Rayleigh sayısının, nanopartikül hacim kesrinin ve iletken bölmenin boyutunun artması, ortalama ısı transferini arttırdığı gözlemlenmiştir. Silindir şeklindeki nanopartiküller en iyi performansı gösterirken, küresel olanlar da ısı transferinin iyileştirilmesi açısından en kötü performansı göstermektedir.

Anahtar Kelimeler

Konjuge doğal konveksiyon, Nanoakışkanlar, Köşe bölme, Sonlu elemanlar yöntemi

Kaynakça

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