İKİ SABİT ISI KAYNAĞIYLA ISITILMIŞ EĞİK KARE BİR KAPALI BÖLGEDE DOĞAL KONVEKSIYONLA ISI TRANSFERİ

Abstract

Bu çalışmada, üniform ısı akısıyla ısıtılmış eğik bir kare kapalı bölge içindeki doğal konveksiyonla ısı transferi, nümerik olarak incelenmiştir. Akışın iki boyutlu, daimi, laminer akış olduğu kabul edilmiştir. Nümerik çözüm için diferansiyel quadrature (DQ) yöntemi kullanılmıştır. Kapalı bölgenin iki duvarı eş sıcaklıkta, alt ve sol duvarı sabit ısı akısıyla kısmi olarak ısıtılmış olup, kalan diğer kısımlar ise adyabatik tutulmuştur. Grashof sayısı 103-106 ve kapalı bölgenin eğim açısı ise 0°? ? ?120° aralığında seçilmiştir. Isıtıcı uzunlukları ?=0.4 olarak seçilmiştir. Elde elden sonuçlara göre ısı transfer miktarı, Grashof sayısı arttıkça artmaktadır. Isıtılan alt ve sol duvarlarda ortalama Nusselt sayısının değeri, eğim açısının küçük değerlerinde, alt duvarda daha yüksek iken, eğim açısının büyük değerlerinde sol duvarda daha büyüktür. Eğim açısı 45° olduğunda, ortalama Nusselt sayısı, her iki duvar içinde eşit olmaktadır.

Keywords

• Doğal konveksiyon, eğik kare kapalı bölge, ısı akısı, DQ yöntemi

NATURAL CONVECTION HEAT TRANSFER IN INCLINED SQUARE ENCLOSURE HEATED WITH TWO CONSTANT HEAT SOURCE

Abstract

Natural convection in an inclined square enclosure heated with a uniform heat flux is investigated numerically in this study. Two-dimensional, steady, laminar flow is considered. Differential Quadrature (DQ) technique was used for numerical solutions. Two walls of enclosure are isothermal and partially heated with constant heat flux and other one is adiabatic. Grashof number is chosen between 103-106 and inclination angle is chosen as 0°? ? ?120°. Length of heaters are ?=0.4. Results show that, quantitiy of heat transfer increases while Grashof number increases. Considering heated bottom and left walls, mean Nusselt number is higher at bottom wall for smaller values of inclination angle and higher at left wall for higher values of inclination angle. For 45° , average Nusselt number is equal for both walls.

Keywords

• Natural convection, inclined square enclosure, heat flux, DQ method

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