Investigation of thermal performance of finned tube evaporator under dry conditions

Bu çalışmada kanatlı borulu bir evaporatörün ısıl performansının analizi kuru şartlar için sayısal olarak yapılmıştır. Havanın ve soğutucu akışkanın değişen özelliklerine göre hava ve soğutucu akışkan tarafındaki taşınım katsayısı hesaplanmıştır. Ayrıca kanat boyunca yüzey sıcaklıkları ve boru yüzey sıcaklıkları hesaplanmıştır. Geçici rejimde evaporatörün toplam ısıl geçirgenliğini (UA) hesaplamak için bir sayısal model oluşturulmuş ve sayısal model Matlab R2010 bilgisayar programında çözülmüştür. Toplam ısıl geçirgenliği, havanın farklı giriş sıcaklıkları ve hızlarında incelenmiştir.Ayrıca kuruluk derecesine göre soğutucu akışkan tarafındaki taşınım katsayısının değişimi incelenmiştir.

Kanatlı borulu evaporatörün kuru şartlar altında ısıl performansının incelenmesi

In this study, analysis of thermal performance of finned tube evaporator under dry conditions has numerically been done. The heat convection coefficient in air and refrigerant sides were calculated by considering their varying properties. In addition, the surface temperature of fin and tubes along the fin were calculated. A numerical model was developed in order to calculate the overall thermal permeability (UA) in transient regime. The numerical model was solved by using Matlab R2010 program. The overall thermal permeability (UA) was examined under different air inlet temperatures and air velocity. In addition, variation of the convection heat transfer coefficient with respect to quality at the refrigerant side was examined.

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