Açık LiBr-su Nem Alma Sisteminde Akış Hızlarının ve Dolgu Kanal Açılarının Sistem Performansı Üzerine Etkisi

Artan yaşam standartlarıyla beraber mekânlarda insanların iç konfor ihtiyacı da artmaktadır. Günümüzde iç konfor şartları yaygın olarak konvansiyonel buhar sıkıştırmalı sistemlerle yapılmasına karşın, bu sistemlerin yüksek oranda elektrik enerjisine bağımlı olması, sınırlı nem kontrolü sağlaması ve iç havayı temizlemede yetersiz olması dikkat çekmektedir. Konvansiyonel buhar sıkıştırmalı soğutma sistemlerinde havanın gizli ısısını gidermek için havayı çiğ noktasının altına kadar soğutmak gerekmektedir. Bu da havanın nemi alınırken hem yüksek miktarda elektrik enerjisi harcanmasına, hem de soğutma sisteminin COP değerinin düşmesine sebep olmaktadır. Bu çalışmada mekanik nem alma sistemlerinin yerine kullanılabilecek, nem alma ve rejenerasyon kolonlarında, daha önce kullanılmamış, polikarbonat dolgu malzemesi kullanılan bir açık sıvı nem alma sistemi deneysel olarak incelenmiştir. Sıvı kurutucu (nem alıcı) olarak kütlece %45’lik LiBr-su (lityum bromür-su) çözeltisi kullanılan sistemde dolgu malzemeleri, 10 mm kalınlıklarındaki polikarbonat levhaların 30°, 45° ve 60° kanal açısı oluşturacak şekilde kesilmesiyle oluşturulmuştur. Sözü geçen kanal açılarının, hava hızının ve sıvı kurutucu debisinin sistemin nem alma verimine, elektriksel ve ısıl performans katsayısına etkisi incelenmiştir.

Effects of Flow Rates and Packing Channel Angles on System Performance of LiBr-aq Open Liquid Desiccant Dehumidification System

Human indoor comfort requirements in places increase with increasing life standarts. Nowadays, despite indoor comfort conditions are provided by conventional vapor compression systems, it is noteworthy that these systems are highly dependent on electrical energy, limited humidity control and inadequate air cleaning. in conventional vapor compression refrigeration systems, it is necessary to cool air below dew point to remove latent heat. This causes both large amount of electricity consumption and low coefficient of performance in system. in this study, an open liquid desiccant dehumidification system, using polycarbonate packing material in dehumidification and regenerator columns, has not been used previously, which can be used instead of mechanical dehumidification systems, was experimentally investigated. The packing material of the system, using 45 mass percent LiBr-aq (lithium bromide-water) solution as desiccant, was formed by cutting polycarbonate sheets 10 mm thickness to form 30°, 45° and 60° channel angles. The effect of these channel angles, air velocity and liquid desiccant flow rate on dehumidification efficiency, electrical and thermal coefficient of performance were investigated.

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