Analysis of inward melting of spheres subject to convection and radiation

Bu çalışmada taşınım ve ışınıma maruz kalan bir kürenin erimesi problemi incelenmiştir. Sıvı faza ait ısı iletim denklemi ile ara yüzey enerji dengesi denklemleri boyutsuz olarak ifade edildikten sonra, hareketli ara yüzey nedeniyle değişken olan problem bölgesi Landau dönüşümü kullanılarak sabitlenmiştir. Boyutsuz denklemler ve sınır koşulları; ara yüzey hızının Biot ve Stefan sayıları, iletim-ışınım parametresi ve boyutsuz sıcaklıklara bağlı olduğunu göstermiştir. Bu yeni sabitlenmiş koordinatlarda ifade edilen problem sonlu farklar yöntemi ile çözülmüştür. Elde edilen sayısal model kullanılarak, erime işlemi üzerine problem parametrelerinin etkisi araştırılmış ve sonuçlar grafiklerle ifade edilmiştir.

Taşınım ve ışınıma maruz kalan bir kürenin içe doğru erimesinin analizi

In the present study, inward spherical melting of a solid subject to convection and radiation initially at the fusion temperature has been investigated. The governing equations for liquid phase and the interface have been expressed in dimensionless form and then, computational domain has been fixed using the well-known Landau transformation. The dimensionless governing equations showed that the velocity of the interface depends on Biot number, Stefan number, conduction-radiation parameter and dimensionless temperatures. The dimensionless liquid phase and interface equations have been solved numerically using a finite difference method. Employing the developed numerical model, the effects of the problem parameters on melting process have been investigated and results have been presented graphically.

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