Sabit ısı akısına sahip bir boruda ısı transferi artımının entropi üretimi üzerindeki etkisi

Bu çalışmada; 62 mm genişliğinde 1200 mm uzunluğunda ebatlara sahip galvanizli sac üzerine değişik çap ve aralıklarda kesilen dirençlere farklı açılar verilerek akım ortamına yerleştirilmiştir. Bu türbülatörler sabit ısı akısı uygulanan bir bakır boru içerisine yerleştirilerek bunların ısı transferi ve entropi üretimi üzerindeki etkileri araştırılmıştır. Çalışma akışkanı olarak hava seçilmiştir. Beş farklı kütlesel debide ve Reynolds sayısının 10000 ila 30000 aralığında deneyler yapılmıştır. Isı transferi ve entropi üretimi arasında doğru orantılı bir ilişki vardır. Deneysel sonuçlarda elde edilen veriler hem Nusselt sayısına hem de entropi üretim oranına göre karşılaştırılmıştır.

The effect of enhancement of heat transfer in a pipe with constant heat flux on entropy generation

In this study, galvanized plates with dimensions of 62x1200 mm, on which cut fins in different diameter and distance, were placed in the flow area. The effect of these turbulators on the heat transfer and entropy generation was investigated by placing in a copper pipe having constant heat flux. Air was used as a working fluid. The experiments were performed for 5 mass flow rates, Reynolds number changed between 10000 and 30000. There is a proportional relationship between dimensionless exergy loss and heat transfer. The results obtained by experiments were compared to both Nusselt number and entropy generation rate.

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