Mehmet Tahir ERDİNÇ, Şaban ÜNAL, Çağrı KUTLU

Çift buharlaştırıcılı ve ejektörlü bir soğutma sisteminin termodinamik analizi

Bu çalışmada, iki buharlaştırıcılı buhar sıkıştırmalı klasik soğutma sisteminin ve bu sistemin ejektörlü hale getirilmesi ile oluşturulan yeni sistemin termodinamik analizi enerji ve momentum denklemleri kullanılarak yapılmıştır. Çalışmada soğutucu akışkan olarak R134a ve bu soğutucu akışkana alternatif olarak geliştirilen R1234yf kullanılmıştır. Farklı yoğuşturucu ve buharlaştırıcı sıcaklıklarında ejektörlü soğutma sistemi etkinliğinin iki buharlaştırıcılı soğutma sistemi etkinliğine göre artışı analiz edilmiştir. Ayrıca her bir sistemin ekserji analizi yapılmış olup sonuçlar grafikler halinde verilmiştir. Yapılan analizlerde ejektörlü soğutma sisteminde elde edilen soğutma etkinliğinin, iki buharlaştırıcılı sistemin soğutma etkinliğinden R134a için %15 ve R1234yf için ise %17 civarında daha fazla olduğu görülmüştür.

Thermodynamic analysis of a refrigeration system with double evaporators and ejector

In this study, theoretical investigations of double evaporator refrigeration system and with adding an ejector to the current system were carried out using energy and momentum equations. The relative increase in COP with respect to the conventional double evaporator refrigeration system was analyzed in terms of condenser and evaporator temperatures. Also exergy analyses of systems were examined and results were showed graphically. In the study, R134a and its potential substitute R1234yf were used. The analyses showed that COP improvements of the proposed system by using ejector as an expansion device were approximately 15% for R134a and about 17% for R1234yf, respectively.

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