ABSORBSİYONLU SOĞUTMA SİSTEMLERİNDE MİKRO KANALLI ABSORBER VE DESORBERİN SAYISAL OLARAK MODELLENMESİ

Yıl 2024, Cilt: 27 Sayı: 5, 1823 - 1836, 02.10.2024

Utku Türkmen , İbrahim Atılgan

https://doi.org/10.2339/politeknik.1341852

Öz

Çalışma kapsamında mikro kanallı ve membran tabanlı absorber ve desorber farklı kanal yükseklikleri (0,5mm – 1mm – 1,5mm), farklı eriyik giriş hızları (0,003-0,072 m/s ve 0,0075-0,0125 m/s), farklı eriyik çeşitleri (LiBr-Su, LiBr/LiNO3/LiI/LiCl-Su, [EMIM][OAc]-Su, LiCl-Su) ve farklı kanal tiplerine (düz kanal, içerisinde bölgesel tümsekler içeren kanal, kanal boyunca kavisler içeren kanal) göre optimizasyon çalışması gerçekleştirilmiş ve sonuçlar değerlendirilmiştir. Sonuç olarak eriyik giriş hızları ve kanal yükseklerinde optimum koşullar belirlenmiş ve özellikle [EMIM][OAc]-Su eriyiğinin absorbsiyon oranı ve basınç düşüşü verilerine göre, LiCl-Su eriyiğinin ise desorbsiyon oranı verilerine göre avantajlı olduğu tespit edilmiştir. Bununla birlikte kanal yapısındaki değişikliklerin absorbsiyon oranlarında anlamlı bir artış sağladığı, bununla birlikte basınç düşüşü konusunda negatif etkisi tüm sonuçlarda görülmüştür.

Anahtar Kelimeler

Absorbsiyonlu soğutma, mikro kanal, iyonik sıvı, absorber, desorber

NUMERICAL SIMULATION OF MICROCHANNEL ABSORBER AND DESORBER IN ABSORPTION REFRIGERATION SYSTEMS

Öz

Within the scope of the study, with respect to different channel heights (0,5mm – 1mm – 1,5mm), different solution inlet velocities (0,003-0,072 m/s and 0,075-0,0125 m/s), different types of solutions (LiBr-Water, LiBr/LiNO3/LiI/LiCl-Water, [EMIM][OAc]-Water, LiCl-Water) and different channel types (Straight channel, channel with localized bumps, channel with curves) an optimization study was studied on micro-channel and membrane-based absorber and desorber, and the results were examined. As a result, optimum conditions were determined with respect to solution inlet velocities and channel heights and it was determined that [EMIM][OAc]-Water solution is advantageous according to the absorption rate and pressure drop data, and LiCl-Water solution is advantageous according to desorption rates. Moreover, the changes in the channel structure provided a significant increase in the absorption rates, and against this caused a negative effect on the pressure drop.

Anahtar Kelimeler

Absorption cooling, micro channel, ionic liquid, absorber, desorber

Kaynakça

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