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

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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