Karşı Akışlı Dolaylı bir Evaporatif Soğutucunun Soğutma Performansının Sayısal Analizi

Abstract

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.

Keywords

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

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

Abstract

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

References

1. [1] Buker, Mahmut Sami; Riffat, Saffa B. Recent developments in solar assisted liquid desiccant evaporative cooling technology—A review. Energy and Buildings, 2015, 96: 95-108.
2. [2] Buker, Mahmut Sami; Mempouo, Blaise; Riffat, Saffa B. Experimental investigation of a building integrated photovoltaic/thermal roof collector combined with a liquid desiccant enhanced indirect evaporative cooling system. Energy Conversion and Management, 2015, 101: 239-254.
3. [3] Bom, G. J., Foster, R., Dijkstra, E., Tummers, M., Evaporative air-conditioning: applications for environmentally friendly cooling, The World Bank, 1999
4. [4] Osma E., Evaporatif Soğutma Sistemlerinin Mekanik Buhar Sıkıştırmalı Soğutma Sistemleri İle Termodinamik Ve Ekonomik Bakımdan Karşılaştırılması, Yüksek Lisans Tezi, Namık Kemal Üniversitesi Fen Bilimleri Enstitüsü, Tekirdağ, 2011.
5. [5] Duan, Z., Zhan, C., Zhang, X., Mustafa, M., Zhao, X., Alimohammadisagvand, B., Hasan, A., Indirect evaporative cooling: Past, present and future potentials, Renewable and Sustainable Energy Reviews, 2012, 16(9), 6823-6850
6. [6] El-Refaie, M. F., Kaseb, S., Speculation in the feasibility of evaporative cooling, Building and Environment, 2009, 44(4), 826-838.
7. [7] Xuan, Y. M., Xiao, F., Niu, X. F., Huang, X., Wang, S. W, Research and application of evaporative cooling in China: A review (I)–Research, Renewable and Sustainable Energy Reviews, 2012, 16(5), 3535-3546.
8. [8] Yang, Y., Cui, G., Lan, C. Q., Developments in evaporative cooling and enhanced evaporative cooling-A review, Renewable and Sustainable Energy Reviews, 2019,113, 109230.

9. [9] Maisotsenko, V., Gillan, L. E., Heaton, T. L., Gillan, A. D, 2003, Washington, DC: U.S. Patent and Trademark Office U.S., Patent No. 6,581,402.
10. [10] Dizaji, H. S., Hu, E. J., Chen, L., Pourhedayat, S, Development and validation of an analytical model for perforated (multi-stage) regenerative M-cycle air cooler, Applied Energy, 2018, 228, 2176-2194.
11. [11] Pandelıdıs, Demis; Pacak, Anna; Anısımov, Sergey. Energy Saving Potential by Using Maisotsenko-Cycle in Different Applications. International Journal of Earth & Environmental Sciences, 2018, 2018.
12. [12] Pandelidis, D., Anisimov, S., Drąg, P., Sidorczyk, M., & Pacak, A., Analysis of application of the M-Cycle heat and mass exchanger to the typical air conditioning systems in Poland. Energy and Buildings, 2018, 158: 873-883.
13. [13] Pandelidis, D., Anisimov, S., Worek, W. M., & Drąg, P., Numerical analysis of a desiccant system with cross-flow Maisotsenko cycle heat and mass exchanger. Energy and Buildings, 2016, 123: 136-150.
14. [14] Zhan, C., Zhao, X., Smith, S., Riffat, S. B., Numerical study of a M-cycle cross-flow heat exchanger for indirect evaporative cooling, Building and Environment, 2011, 46(3), 657-668.
15. [15] Zhao, X., Li, J. M., Riffat, S. B., Numerical study of a novel counter-flow heat and mass exchanger for dew point evaporative cooling, Applied Thermal Engineering, 2008, 28(14-15), 1942-1951.
16. [16] Riangvilaikul, B., Kumar, S., Numerical study of a novel dew point evaporative cooling system, Energy and Buildings, 2010, 42(11), 2241-2250.
17. [17] Wang, L., Zhan, C., Zhang, J., Zhao, X. (2018). The energy and exergy analysis of counter-flow regenerative evaporative cooler. Thermal Science, 2018.
18. [18] Buker, Mahmut Sami; Riffat, Saffa B. Performance analysis of a combined Building Integrated PV/T Collector with a liquid desiccant enhanced dew point cooler. Energy Procedia, 2016, 91: 717-727.
19. [19] Zhao, X., Duan, Z., Zhan, C.,Riffat, S. B., Dynamic performance of a novel dew point air conditioning for the UK buildings, International Journal of Low-Carbon Technologies, 2009, 4(1), 27-35.
20. [20] Zhao, X., Yang, S., Duan, Z., Riffat, S. B., Feasibility study of a novel dew point air conditioning system for China building application, Building and Environment, 2009, 44(9), 1990-1999.
21. [21] Zhan, C., Zhao, X., Duan, Z., Riffat, S. B., Numerical study on indirect evaporative cooling performance comparison between counterflow and crossflow heat exchangers, International Journal of Low-Carbon Technologies, 2011, 6(2), 100-106.
22. [22] Çengel Y.A., Cımbala J.M., Giriş ve Temel Kavramlar, Akışkanlar Mekaniği Temelleri ve Uygulamaları, Güven Kitabevi, Ankara, 2008
23. [23] Zhao, X., Liu, S.,Riffat, S. B., Comparative study of heat and mass exchanging materials for indirect evaporative cooling systems, Building and Environment, 2008, 43(11), 1902-1911.
24. [24] Çengel Y.A. , Ghajar A. J., Zorlanmış İç Taşınım, Isı ve Kütle Transferi Esaslar ve Uygulamalar, Palme Yayıncılık, Ankara, 2019