Thermodynamic and Exergy Analysis of an Absorptıon Cooling System for Different Refrigerants

Year 2020, , 93 - 103, 31.01.2020

Dilek Nur Özen , Kemal Çağrı Yağcıoğlu

https://doi.org/10.31202/ecjse.594641

Cited By: 1

Abstract

In absorption cooling systems, the compression of the working fluid is
not made by the compressor but by a system consisting of absorbers, pumps and
generators. The fact that the compressor is not used for compression reduces
the power required for this process. In this case, absorption cooling systems
are very useful when used with renewable energy sources. In this study,
thermodynamic and exergy analysis of the system was performed to see the
effects of different refrigerant solutions on the performance of an absorption
cooling system. In the absorption cooling system for Lithium bromide-Water
(LiBr-H₂O), ammonia-water (NH₃-H₂O),
ammonia-lithium nitrate (NH₃-LiNO₃) and ammonia-sodium
thiocyanate (NH₃-NaSCN) fluid couples, the Coefficient of
Performance (COP) and Exergy Efficiency (%) of the system were examined for
each fluid pair by analyzing at different generator, evaporator and absorber
temperatures. Analysis results indicate that the LiBr-H₂O solution
pair showed better performance (higher COP and exergy efficiency) than the
other solution pairs (NH₃-H₂O, NH₃-LiNO₃,
NH₃-NaSCN).

Keywords

Exergy, ammonia/NH3, LiBr/H2O, ammonia/NaSCN, absorption refrigeration system

Farklı Soğutucu Akışkanlar için Bir Absorbsiyonlu Soğutma Sisteminin Termodinamik ve Ekserji Analizi

Abstract

Absorpsiyonlu soğutma sistemlerinde çalışma
akışkanının sıkıştırma işlemi kompresörle değil absorber, pompa ve generatörden
oluşan bir sistemle yapılmaktadır. Sıkıştırma işlemi için kompresör
kullanılmaması bu işlem için ihtiyaç duyulan gücü azaltmaktadır. Bu durumda
absorbsiyonlu soğutma sistemleri yenilenebilir enerji kaynakları ile
kullanıldığında oldukça kullanışlı olmaktadır. Bu çalışmada farklı soğutucu
akışkan çözeltilerinin bir absorpsiyonlu soğutma sisteminin performansı
üzerindeki etkilerini görebilmek için sistemin termodinamik ve ekserji analizi
yapılmıştır. Lityum bromür-Su (LiBr-H₂0), amonyak-su (NH₃-H₂0),
amonyak-lityum nitrat (NH₃-LiNO₃) ve amonyak-sodyum
tiyosiyanat (NH₃-NaSCN) akışkan çiftleri için absorbsiyonlu soğutma
sisteminde farklı jeneratör, buharlaştırıcı ve absorber sıcaklıklarında analiz
yapılarak sistemin Soğutma Tesir Katsayısı (STK) ve Ekserji Verimleri (%) her
bir akışkan çifti için incelenmiştir. Analiz sonuçları LiBr-H₂O
çözelti çiftinin diğer akışkan çiftlerine (NH₃-H₂O, NH₃-LiNO₃,
NH₃-NaSCN) göre daha iyi bir performansa sahip olduğunu
göstermiştir.

Keywords

Ekserji, NH3, LiBr/H2O, NH3/NaSCN, absobsiyonlu soğutma sistemi

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