Al2O3 Nanopartiküllü ve Nanopartikülsüz Parafinin Erime Davranışları Üzerine Sayısal Bir Çalışma

Faz Değiştiren Malzemelerin (FDM) kullanımı ısıl enerji depolamadaki en verimli yöntemlerden biridir. Organik FDM’ler arasında olan parafin, kolay ulaşılabilir olması ve yüksek ısı depolama kapasitelerine sahip olması sebebiyle ısıl depolama uygulamalarında sıklıkla kullanılmaktadır. Ancak düşük ısıl iletkenlikleri sebebiyle sistemlerin ısıl şarj/deşarj (erime/katılaşma) hızını önemli ölçüde sınırlamaktadır. Parafinin ısıl iletkenliğini arttırmak amacıyla uygulanan birçok yöntem bulunmaktadır. Bu çalışmada dikdörtgen bir erime alanı içinde saf parafin (Rubitherm RT50) ve kütlece %10 Al2O3 nanopartikül katkılı parafinin erime süreçleri sayısal olarak araştırılmıştır. Karşılaştırma yapabilmek için, hem erime sıcaklığı 50 °C olan saf parafin hem de nanopartikül katkılı parafin için dikdörtgen alanın duvar sıcaklığının 65 °C, 70 °C ve 75 °C’ye arttırılmasının toplam erime zamanına etkisi incelenmiştir. Hesaplamalı Akışkanlar Dinamiği (HAD) yaklaşımının kullanıldığı bu çalışmada, sayısal analizleri yapmak için ANSYS Fluent yazılımı kullanılmıştır Çalışma sonucunda Al2O3 nanopartikül kullanımının parafinin ısı transfer hızını arttırdığı tespit edilmiştir.

Anahtar Kelimeler:

Faz değiştiren malzeme, parafin, Al2O3 nanopartikül, hesaplamalı akışkanlar dinamiği

A Numerical Study on the Melting Behaviors of Paraffin with and without Al2O3 Nanoparticles

One of the most effective methods of thermal energy storage is the use of Phase Change Materials (PCM). Paraffin, which is among the organic PCMs, is frequently used in thermal storage applications due to its easy accessibility and high heat storage capacity. However, it significantly limits the thermal charge / discharge (melting / solidification) rate of systems caused by their low thermal conductivity. There are many methods applied to enhance the thermal conductivity of paraffin. In this research, the melting processes of pure paraffin (Rubitherm RT50) and paraffin containing 10% Al2O3 nanoparticle in a rectangular melting area were numerically investigated. For comparison, the effect of increasing the wall temperature of the rectangular area to 65 ° C, 70 ° C and 75 ° C on the total melting time was investigated for both pure paraffin (melting temperature 50 ° C) and paraffin with nanoparticle additives. In this study, in which the Computational Fluid Dynamics (CFD) approach was used, ANSYS Fluent software was used to perform numerical analysis. Consequently it was determined that the use of Al2O3 nanoparticles improved the rate of paraffin heat transfer.

Keywords:

Phase change materials, paraffin, Al2O3 nanoparticle, computational fluid dynamics,

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