Ters Basamak Şekilli Kanal İçerisindeki Laminer Akışın Eşlenik Isı Transferi Karakteristiği

Bu çalışma iletken katı bir alt duvarı olan ters basamak şekilli bir kanal için, katının akışkana göre iletim oranı, katı duvarın kalınlığı, Prandtl ve Reynolds sayılarının eşlenik ısı transferine etkilerini incelemektedir. 2006 yılında Kanna ve Das aynı problem için bir durum çalışması yapmış olmalarına rağmen, sunulan bu çalışmanın da dâhil olduğu sonraki yıllarda yapılan karşılaştırma çalışmaları Kanna ve Das’ın sonuçlarının tartışmalı olduğunu ortaya koymuştur. Ramsak çalışmasında “kişisel iletişim sırasında Profesör Kanna’nın elde ettikleri sonuçların muhtemelen yanlış olduğunu teyit ettiğini” belirtmektedir. Bu çalışmada sunulan ara yüzey boyunca sıcaklık ve Nusselt sayısı değişimleri Ramsak’ın elde ettikleri ile mükemmel bir uyum içerisindedir. Bu makalede sunulan analizler, her ne kadar Prandtl sayısındaki düşüşün ve katının akışkana iletim oranındaki artışın ara yüzey sıcaklığı üzerindeki genel etkisinin katı duvardaki incelmeyle benzer olduğunu ortaya koysa da, ilk iki parametrenin etkileri resirkülasyon bölgesinde sınırlıdır.

Conjugate Heat Transfer Characteristics of Laminar Flows Through a Backward Facing Step Duct

Present study investigates the effects of solid to fluid conductivity ratio, Prandtl and Reynolds numbers, and solid wall thickness on conjugate heat transfer for a backward facing step duct with a conductive solid bottom wall. Although Kanna and Das performed a case study in 2006 for the same problem, the benchmark studies conducted later including the present one revealed that their results are arguable. Ramsak states in a study “Professor Kanna has confirmed in personal communication that their results are probably wrong”. The temperature and Nusselt number variations along the solid-fluid interface presented here are in excellent agreement with those obtained by Ramsak. The analyses presented here reveal that even though the decrease in Pr and the increase in solid to fluid conductivity ratio have similar global influence with the thinning wall on the interface temperature, the influence of the former parameters are limited in recirculation zone.

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