Elif BÜYÜK ÖĞÜT, Medet KILIÇTEPE, Hakan F. ÖZTOP

Effects of Viscosity Models on Natural Convection of Cu-water Nanofluids in a Triangular Cavity

Bu çalışmada, üçgen bir kavite içindeki bakır-su bazlı nanoakışkanların laminer doğal konveksiyon akışı sonlu hacimler metoduyla nümerik olarak incelenmiştir. Kavitenin yan duvarları farklı şekilde ısıtılmış olup, alt duvarı dalgalı ve yalıtılmıştır. Yönetici parametre olarak Grashof sayısı 104 - 106 aralığında, katı partiküllerin hacim fraksiyonu 0, 0.02, 0.04 aralığında ele alınmıştır. Nanoakışkanların viskozitesinin hesaplanmasında Batchlor, Brinkman, Pak ve Cho, Einstein and Maiga vd. modelleri kullanılmıştır. Sonuçlar göstermektedir ki, ısı transfer miktarı, katı hacim fraksiyonu ve Grashof sayısının artmasıyla neredeyse lineer olarak artmaktadır. En yüksek ısı transfer oranı Batchelor modeli kullanıldığında ortaya çıkmaktadır.

Üçgen Bir Kavite İçerisindeki Bakır-Su Nanoakışkanların Doğal Konveksiyon Üzerinde Viskozite Modellerinin Etkisi

In this study, laminar natural convection heat transfer and fluid flow in a triangular cavity filled with Cu-water nanofluids is studied numerically by using finite volume method. Bottom wall of the cavity is taken as adiabatic while inclined walls have different temperature which are isothermally heated. As governing parameters, Grashof number is taken in the range of 104 - 106, the solid particle volume fraction values are taken as 0, 0.02 and 0.04. In the calculation, different viscosity models such as Batchelor, Brinkman, Pak and Cho, Einstein and Maiga et al. are tested on natural convection heat transfer and fluid flow. It is observed that heat transfer increases almost linearly with increasing of solid volume fraction and Grashof number. Also, another finding is that the higest heat transfer is observed when Batchelor model is used.

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