LiBr-H2O AKIŞKAN ÇİFTİNİ KULLANAN BİR ABSORBSİYONLU SOĞUTMA SİSTEMİ İÇİN TERMODİNAMİK VE EKSERJİ ANALİZİ

Yıl 2019, Cilt: 7 Sayı: 1, 135 - 145, 01.03.2019

Dilek Nur Özen , Kemal Çağrı Yağcıoğlu

https://doi.org/10.15317/Scitech.2019.187

Öz

Absorpsiyonlu
soğutma sistemleri soğutma ve ısıtma amaçlı kullanılarak, çevre korumasının
yanında enerji tasarrufu da sağlamaktadır. Sistem diğer soğutma sistemlerine
göre daha karmaşık ve soğutma etki katsayısı daha küçük olmasına rağmen atık
enerjilerin ve yenilenebilir enerjilerin değerlendirilmesinde en uygun
sistemlerdir. Sıkıştırma işlemi diğer sistemlerde kompresörle yapılmasına
rağmen, absorpsiyonlu sistemlerde bu işlem absorber ve kaynatıcıdan oluşan bir
sistemle gerçekleştirilir. Bu çalışmada, bir absorbsiyonlu soğutma sisteminin termodinamik ve
ekserji analizi, LiBr-H2O akışkan çifti için yapılmıştır. Analiz Matlab
bilgisayar programında oluşturulan bir matematik model ile
gerçekleştirilmiştir. Farklı kaynatıcı, buharlaştırıcı ve absorber çıkış
sıcaklıklarında sistemin Performans Katsayısı (STK) ve Ekserji kaybı
incelenmiştir. Çalışmanın sonuçları artan kaynatıcı (T_k) ve buharlaştıcı
sıcaklıklarının (T_b)  ekserji
kaybını arttırdığını ve absorber çıkış sıcaklığının (T_abs) artması
ile ekserji kayıplarının azaldığını göstermiştir. Ayrıca kaynatıcının çalışma
koşullarının çoğunda ekserji kaybının en yüksek oranı sergilediği görülmüştür.

Anahtar Kelimeler

Absorbsiyonlu Soğutma, Ekserji, Enerji, Entropi, LiBr/H2O

Thermodynamic and Exergy Analysis of an Absorption Cooling System for Libr-H2O Fluid Couple

Öz

Absorption cooling systems are used for cooling and
heating, saving energy as well as environmental protection. Although the system
is more complex than the other cooling systems and the cooling efficiency
coefficient is smaller, it is the most suitable system for evaluating waste and
renewable energies. Although compression is done by compressor in other
systems, in absorptive systems this process is done with a system consisting of
absorber and generator.  In this study, an energy and exergy analysis of
an absorbent refrigeration system was made for the LiBr-H2O fluid couple. The
analysis was carried out using a mathematical model developed in the Matlab
program. The Performance Coefficient (STK) and Exergy loss of the system were
investigated at different generator, evaporator and absorber temperatures. The
results of the study showed that loss of exergy was reduced by decreasing Tg,
Te and increasing Tabs temperatures, and the loss of exergy in most of the
operating conditions of the generator exhibited the highest rate.

Anahtar Kelimeler

Absorption refrigeration, Energy, Entropy, Exergy, LiBr/H2O

Kaynakça

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