Karbondioksitli Kaskad Soğutma Sistemlerinin Enerji Performans Değerlendirilmesi

Yıl 2020, Cilt: 4 Sayı: 1, 22 - 32, 13.03.2020

Tuğba Kovacı

https://doi.org/10.31200/makuubd.669252

Öz

Bu
çalışmada, R744 + R717 / R1234ze / R134a / R152a soğutkanları kullanılan dört
farklı kaskad sisteminin karşılaştırılması sunulmuştur. Analiz -45°C’den
-20°C’ye değişen farklı evaporatör sıcaklıklarında ve 30°C’den 50°C’ye değişen
farklı kondenser sıcaklıklarında gerçekleştirilmiştir. Evaporatör sıcaklığı
25°C arttırıldığında, tüm sistemin soğutma performansı (COP_SYS)
değeri yaklaşık %60 ila %64 arasında artmış ve kompresör gücü de yaklaşık %38
oranında azalmıştır. Kondenser sıcaklığının 20°C arttırılması, COP_SYS'de
%29 34 oranında bir azalmaya ve kompresör gücünde yaklaşık %38-50 oranında bir
artışa neden olmuştur. Sonuçlara göre, düşük küresel ısınma potansiyeli (GWP)
ve yüksek soğutma performansı değerine sahip olan R744/R717 soğutucu
akışkanları kullanılan "sistem 1" kombinasyonunun, incelenen diğer
kaskad soğutma sistemlerinden daha verimli olduğunu belirlenmiştir. 

Anahtar Kelimeler

Kaskad Soğutma, R744, COP

Energy Performance Assessment of CO2 Cascade Refrigeration Systems

Öz

In
this study, a comparison of the four different cascade systems using
R744+R717/R1234ze/R134a/R152a refrigerant pairs has been presented. The
analysis has been performed for different evaporator temperatures ranged from
-45 up to -20°C, and different condenser temperatures ranged from 30 up to
50°C. When the evaporator temperature has been increased by 25°C, the system
cooling performance (COP_SYS) value has increased by about 60% to
64%, and the compressor work has decreased by about 38%. Increasing the
condenser temperature by 20°C has resulted in a decrease in COP_SYS
of 29-34% and an increase in compressor work by about 38% to 50%. According to
the results, the combination of “system 1” using R744/R717 refrigerants which
having low GWP and high cooling performance has been determined more efficient
than other examined cascade refrigeration systems. 

Anahtar Kelimeler

Cascade Refrigeration, R744, COP

Kaynakça

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