Karbondioksitli Kaskad Soğutma Sistemlerinin Enerji Performans Değerlendirilmesi

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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