Bir Yatay Gizli Isıl Enerji Depolama Biriminde Eksantriklik: İç Boru Geometrisinin Etkileri

Year 2022, Volume: 63 Issue: 709, 672 - 688, 30.12.2022

Ozgur Bayer

https://doi.org/10.46399/muhendismakina.1139121

Abstract

Güneş enerjisinin kesintili karakteristiği, farklı sektörlerde süreklilik arz eden ve güvenilir enerji sağlamak amaçlı uygulamaların geliştirilmesini teşvik etmektedir. Faz değiştiren malzemelerin kullanıldığı gizli ısıl enerji depolama çözümleri, boyutları, maliyetleri ve sabite yakın çalışma sıcaklıkları nedeniyle araştırmacıların ana odak noktası olmuştur. Eş merkezli LTES ünitelerinde performans iyileştirmesi için temel yöntemlerden bir tanesi, eksantrikliği sağlamak ve ünitenin tepki ve şarj süresini azaltmak için iç borunun konumunu değiştirmektir. Bu çalışmada, daire, kare ve üçgen şeklindeki farklı iç boru geometrileri için eksantriklik uygulaması gerçekleştirilmiştir. Tüm durumlar için zamana bağlı erime davranışı hız, sıcaklık ve sıvı fraksiyonu konturları incelenerek sunulmuştur. Tüm durumlar için en düşük erime süresine sahip üçgen eksantrik tasarım ile erime süresinin en optimum şekilde iyileştirildiği gözlemlenmiştir. Üçgen tasarımda şarj süresi yaklaşık %50 azalırken, daire ve kare tasarımlarda bu azalma daha az belirgindir. Eksantrikliğin kullanılmasından kaynaklanan doğal konveksiyon performansındaki artış, erime süresindeki iyileşmelerin temel nedenidir.

Keywords

FDM, doğal taşınım, erime, termal pil

Supporting Institution

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Project Number

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Thanks

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Eccentricity in a Horizontal Latent Thermal Energy Storage Unit: Effects of Inner Tube Geometry

Abstract

The intermittency of solar energy has resulted in a urge to implement a buffer for providing constant and reliable energy in different sectors. Latent thermal energy storage solutions that use phase change materials have been the main focus of researchers due to their size, cost and near-constant operating temperatures. One of the main ways of performance improvement in concentric LTES units is changing the location of inner tube to introduce eccentricity and decrease the response and charging time of the unit. In this study, the eccentricity is implemented for different inner tube geometries, circle, square and triangle. The time dependent melting behavior of all the cases are presented by investigating the velocity, temperature and liquid fraction contours. The melting time is improved for all the cases with the triangle eccentric design having the lowest melting time. The charge time in the triangular case is decreased nearly 50% while the decrease is less significant for the circle and square designs. The natural convection improvement due to employment of eccentricity is the reason for the enhancements.

Keywords

PCM, Natural convection, melting, thermal battery

Project Number

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