Numerical analysis of natural convection heat transfer from partially open cavities heated at one wall

Bu çalışmada, bir duvarı ısıtılmış kısmi açık hacimlerden doğal konveksiyonla ısı transferi sayısal olarak incelenmiştir. Çalışmanın amacı, uniform ısı akısı (q″) altındaki boşluk içerisinde, sürekli şartlarda, farklı açıklık oranları (AO), eğim açıları (EA) ve geometrik oranlarda (GO), üstten ve merkezden açık konumlar için doğal konveksiyonla ısı trasnsferinin incelenmesidir. Bu amaçla, kütle, momentum ve enerji korunum denklemleri uygun sınır şartları kullanılarak PHOENICS kodu ile çözülmüştür. Elde edilen sonuçlara göre, açıklık oranının artması ve eğim açısının azalmasıyla, ortalama ısı transfer katsayısı artmakta ve ortalama duvar sıcaklığı azalmaktadır. Geometrik oranın maksimum, açıklık oranının 0.75 ve eğim açısının -10° olduğu durumda en iyi ısı transferi elde edilmiştir.

Bir duvarı ısıtılmış kısmi açık hacimlerden doğal konveksiyonla ısı transferinin sayısal analizi

In this study, the heat transfer by natural convection from partially open cavities with one wall heated was investigated numerically. The aim of this study was the steady state investigation of the natural convection heat transfer inside the cavity under uniform heat fluxes (q″), different opening ratios (OR), tilt angles (θ) and cavity aspect ratios (AR) for top and center opening positions. For this purpose, the equations of conservation of mass, momentum and energy were solved using adequate boundary conditions by means of the PHOENICS code. According to the results obtained, the average heat transfer coefficient increases and the average wall temperature decreases, with the increase in opening ratio and decrease in the tilt angle. Best heat transfer was obtained with the maximum aspect ratio for opening ratio of 0.75 and tilt angle of -10°.

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