Ekrem ÖZDEN, Hacı PARLAMIŞ, Mahmut Sami BÜKER

Karşı Akışlı Dolaylı bir Evaporatif Soğutucunun Soğutma Performansının Sayısal Analizi

Bu çalışmada, geleneksel mekanik buhar sıkıştırmalı soğutma sistemlerine alternatif olabilecek, karşı akışlı dolaylı bir evaporatif soğutucunun sayısal analizi ele alınmıştır. Tasarlanan evaporatif soğutucunun farklı parametrelerdeki soğutma etkinlik değerlerini bulmak için simülasyonlar gerçekleştirilmiştir. Simülasyon sonuçlarına göre, soğutma etkinliklerinin, büyük oranda hava kanallarının boyutlarına, giriş havasının hızına ve çalışma-giriş hava oranına bağlı olduğu görülürken, besleme suyu sıcaklığının etkisinin ise çok az olduğu gözlemlenmiştir. Konya ilinde soğutma ihtiyacının en fazla olduğu Temmuz ayı hava koşulları göz önünde bulundurularak yapılan analiz sonuçlarında, sistemin yaş termometre etkinliği 1.15, çiğlenme noktası etkinliği ise 0.80 olarak bulunmuştur.

Anahtar Kelimeler:

Karşı akışlı evaporatif soğutucu, Sayısal analiz, M-çevrimi, EES

Numerical study on cooling performance of a counter-flow indirect evaporative cooler

In this study, numerical analysis of a counter-flow indirect evaporative cooler, which could be an alternative to conventional mechanical vapor compression cooling systems, is performed and the results are discussed. Simulations were carried out to determine the cooling effectiveness of the analysed evaporative cooler with respect to size of the air ducts, the speed of the inlet air and the ratio of working-inlet air and effect of the feed water temperature. According to the simulation results, it was observed that the cooling effetiveness values were mainly dependent on the size of the air ducts, the speed of the inlet air and the ratio of working-inlet air, while the effect of the feed water temperature was found to be miniscule. Simulations were performed under prevailing weather conditions of Konya city, taking into account the weather conditions in the month of July when the need for space cooling is the highest in demand. The results of the analysis showed that the wet bulb effectiveness of the system was 1.15 while the dew point effectiveness was 0.80, respectively.

Keywords:

Counter flow evaporative cooler, M-cycle, EES, Numerical analysis,

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