Müslüm ARICI, Metin AKYOL, Elif BÜYÜK ÖĞÜT

YAN DUVARLARI DALGALI EĞİK BİR KARE KAVİTE İÇİNDEKİ NANOAKIŞKANLARIN DOĞAL KONVEKSİYONU

Bu çalışmada yan duvarları dalgalı, eğik kare bir kavite içindeki, su bazlı nanoakışkanın doğal konveksiyonu nümerik olarak incelenmiştir. Kapalı bölgenin üst ve alt duvarları adyabatik, yan duvarları ise farklı sabit sıcaklıkta tutulmuştur. Bu çalışmada Cu, CuO ve Al2O3 olarak üç farklı nanaopartikül kullanılmıştır.Kapalı bölgenin eğim açısı saat ibresi yönünde 00, 450 and 90o olarak seçilmiş olup, genlik değerleri 0.05,0.075, and 0.1 için tek ve üç dalgalı duvarlara sahip kavite için analizler yapılmıştır. Sonuçlara göre, nanopartikül hacimsel konsantrasyonu ve Rayleigh sayısının artmasıyla ısı transfer oranı artmaktadır. Ayrıca, dalga sayısındaki artışla beraber ısı transfer miktarı önemli ölçüde artmaktadır

NATURAL CONVECTION OF NANOFLUIDS IN AN INCLINED SQUARE CAVITY WITH SIDE WAVY WALLS

Abstract: In this study, a numerical simulation is performed to study natural convection of water based nanofluid in aninclined square side wavy walls cavity. The the top and bottom walls of the cavity are assumed to be adiabatic and theside walls are at different constant temperatures. Three different nanoparticles, Cu, CuO and Al2O3 are used in the study.The computations are conducted for solid volume fractions of 0%, 5% and 10% and for Rayleigh number of 104, 105 and 106. The analyses were conducted for 00, 450 and 90oinclination angle for enclosed cavity, 0.05, 0.075, and 0.1amplitude and 1 and 3 undulation numbers. The results show that heat transfer rate increases with the increase innanoparticle volume fraction and Rayleigh number. Additionally, it is observed that increasing undulation numberincreases heat transfer rate significantly.Keywords: Natural convection, nanofluid, inclination cavity, wavy wall.

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