Kademeli Soğutma Sistemlerinde Soğutucu Akışkan Seçimi İçin Bir Uygulama

Year 2015, Volume: 3 Issue: 1, - , 31.05.2015

Reşat Selbaş

Abstract

Bu çalışmada kaskad soğutma sisteminin termodinamik analizi yapılmıştır. Soğutma kapasitesi 1 kW olarak kabul edilmiştir. Kondenser sıcaklığı 50 ËšC ile 60 ËšC arasında, evaporator sıcaklığı -30 ËšC ile -40 ËšC arasında değiştirilmiştir. Kaskad soğutma sisteminde soğutucu çifti olarak R134a-R404A, R134a-R407C, R404A-R410A, R404A-R507, R407C-R410 A kullanılmıştır. Bu soğutucu akışkan çiftlerinin ozon tabakasına ve çevreye yıkıcı etkisi yoktur. Kaskad soğutma sisteminin COP değerleri ve tersinmezlik değerleri belirlenmiştir. Bütün akışkan çiftlerin arasında en yüksek verim ve en düşük tersinmelik oranı R134a-R407C akışkan çiftinde elde edilmiştir.

Keywords

Cascade refrigeration, Thermodynamic analysis, COP, exergy

An Application for Refrigerant Selecting In the Cascade Refrigeration Systems

Abstract

In this study, energy and exergy analysis of a cascade refrigeration system was carried out. It is assumed that the refrigeration load is 1 kW. The temperature in condenser has been used between 50 ËšC to 60 ËšC, and the temperature in evaporator was changed between -30 ËšC to -40 ËšC. Refrigerant couples used in the cascade refrigeration system are R134a-R404A, R134a-R407C, R404A-R410A, R404A-R507, and R407C-R410A. These refrigerant couples are new generation refrigerant couples that are non-destructive to environment and to the ozone layer. The COP values and irreversibility values of the cascade refrigeration system were determined. In all cases, the refrigerant couple R134a-R407C has the highest COP and lowest irreversibility.

Keywords

Cascade refrigeration, Thermodynamic analysis, COP, exergy

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