Study of simultaneously developing flow and temperature field in rectangular ducts with constant wall temperature

Bu çalışmada dikdörtgen kanalların girişinde hidrodinamik ve termal yönden gelişmekte olan akışın akış ve ısı transferi karakteristikleri teorik olarak incelenmiştir. Hız bileşenlerinin hesaplanmasında parabolik momentum denklemleri kullanılmıştır. Sıcaklık dağılımın belirlenmesinde ise enerji denkleminin parabolik biçimi kullanılmıştır. Basınç dağılımı, süreklilik ve momentum denklemlerinden elde edilen Poission denklemi yardımı ile belirlenmiştir. Sonlu fark denklemlerinin sayısal çözümlemelerinde Newton-Raphson metodu kullanılmıştır. Sayısal sonuçlar Reynold sayısının 250 $\leq $ Re $\leq $ 2250 aralığında 1/3, 2/3 ve 3/3 kenar oranları için verilmiştir. Analizin doğruluğu literatürden elde edilen tam gelişmiş akışın Nusselt sayıları ile kıyaslanarak sağlanmıştır.

Dikdörtgen kesitli kanallarda sabit duvar sıcaklığında eşzamanlı gelişen akışın ısı transferinin incelenmesi

In this research, the heat transfer and flow friction characteristics of hydrodynamically and thermally developing flows at the entrance of rectangular ducts have been theoretically studied. In calculating components of velocity, parabolic momentum equations'were used. Temperature field was also determined using parabolic form of energy equation. Besides, pressure distribution was calculated by means of a Poisson equation, which is obtained from combination of momentum and continuity equations. In numerical solution of finite difference equations, Newton-Raphson method was used. Numerical results were presented for channels with 1/3, 2/3 and 3/3 aspect ratio and range of Reynolds number 250 $\leq $ Re $\leq $ 2250. Accuracy of the analysis was confirmed by comparing the fully developed Nusselt numbers obtained in this study with the literature.

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