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Abstract

In this study, the variation of optimal inter-stage pressure of two stage transcritical CO2 cooling cycle with evaporating temperature and gas cooler outlet temperature of CO2 is theoretically studied. However optimum gas cooler pressure values are used to obtain reliable optimum inter-stage pressure values. A correlation published in the relevant literature is used for calculation of optimum gas cooler pressure at each parametric analysis. The variations of optimal inter-stage pressures with evaporation and gas cooler outlet temperature of CO2 are presented graphically. Furthermore parametric analysis study results are formulated with an equation which has 0.81 regression value

Keywords

• CO2, transcritical, optimum, inter-stage, pressure, cooling

İki Kademeli Kritik Nokta Üstü CO2 Çevrimli Soğutma Sistemlerinde Optimum Ara Kademe Basıncının İncelenmesi

Öz

Bu çalısmada, iki kademeli, kritik nokta üstü çevrimli ve CO2 soğutucu akıskanlı soğutma sistemleri için optimum ara kademe basıncının, CO2’in evaperatördeki buharlasma sıcaklığı ve gaz soğutucudan çıkıs sıcaklığı ile değisimi incelenmistir. Ara kademe basıncının optimum değerlerinin elde edilebilmesi amacıyla, sistem verimliliğini maksimum yapan, gaz soğutucu basınç değerleri analizde kullanılmıstır. Bu amaçla literatürde verilmis bir korelasyon kullanılmıstır. Her parametrik analizde, optimum gaz soğutucu basıncı dikkate alınarak, optimum ara kademe basıncı değerleri elde edilmistir. Optimum ara kademe basıncının buharlasma sıcaklığı ve gaz soğutucu çıkıs sıcaklığı ile değisimi sunulmustur. Ayrıca parametrik analiz sonuçları, regresyon değeri 0.81 olan bir matematiksel ifade ile genellestirilmistir.

Anahtar kelimeler: CO2, kritik nokta üstü, optimum, ara kademe, basınç, soğutma.

Anahtar Kelimeler

• CO2, kritik nokta üstü, optimum, ara kademe, basınç, soğutma.

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