Effects of joule heating on MHD natural convection in non-isothermally heated enclosure

Bu sayısal çalışmada, farklı Rayleigh ve Hartmann sayıları için sağ cidarı değişken sıcaklığa sahip kare oyuktadoğal taşınım ısı transferine joule etkisi incelendi. Oyuğun yatay cidarları yalıtımlı olarak düşünüldü sol taraf ise dahasoğuk kabul edilmiştir. Denklemlerin çözümü için sonlu hacim metodu kullanıldı. Hesaplamalar, farklı Rayleighsayıları ($Ra = 10^4, 5x10^4$ ve $10^5$ ), joule parametresi (J = 0.0, 3.0 ve 5.0) ve Hartmann sayısı (Ha = 0, 10, 20 ve 50) için yapıldı. Elde edilen sonuçlar, akım çizgileri, eş sıcaklık eğrileri sıcaklık ve hız profilleri ve ortalama Nusselt sayılarıile verildi. Akış yoğunluğu doğrusal olmayan doğrusal olmayan sınır şartından dolayı oyuğun sağ köşesinde dahadüşüktür. Hem Hartmann sayısı hem de Joule parametresi ısı transferi ve akış üzerinde etkilidir.

Değişken sıcaklık etkisinde bulunan bir oyukta MHD doğal taşınımına joule ısıtmasının etkisi

In this numerical work, effects of joule heating on natural convection in non-linearly heated squareenclosure from right vertical wall were investigated for different Rayleigh numbers and Hartmann numbers. Thecavity was considered with adiabatic horizontal walls and cooled left wall. Finite volume method was used to solvegoverning equations. The calculations have been performed for different Rayleigh numbers ($Ra = 10^4, 5x10^4$ ve $10^5$),Joule parameter (J = 0.0, 3.0 and 5.0) and Hartmann number (Ha = 0, 10, 20 and 50). Obtained results are illustratedwith streamlines, isotherms, temperature and velocity profiles and mean Nusselt number. It is found that the flowbecome weaker near the right corner of the cavity due to non-isothermal boundary condition. Both Hartmann numberand Joule parameter have important effect on heat transfer and fluid flow.

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