FARKLI TİPTE NANOPARÇACIKLARLA KATKILANAN A82 ORGANİK FAZ DEĞİŞTİREN MALZEMENİN TERMAL ÖZELLİKLERİNİN BELİRLENMESİ

Öz

Yüksek enerji depolama kapasitesine sahip organik faz değiştiren malzemelerin uygulamada etkin bir biçimde kullanılabilmeleri için düşük ısıl iletkenliklerinin iyileştirilmesi gerekmektedir. Bu çalışmada organik bir faz değiştiren malzeme içerisine nanoparçacıklar katkılanarak ısıl iletkenliğin iyileştirilmesi amaçlanmıştır. Kullanılan nanoparçacıkların tip, boyut ve şeklinin termal özellikler (ısıl iletkenlik, gizli ısılar, erime/katılaşma sıcaklıkları) üzerindeki etkisi sistematik olarak incelenmiştir. Karbon tabanlı nanoparçacık katkılanan organik faz değiştiren malzemelerin ısıl iletkenliklerinde görülen iyileşmenin metal tabanlı nanoparçacık katkılanan faz değiştiren malzemelere göre önemli derecede daha yüksek olduğu belirlenmiştir. %5 GNP katkılanan faz değiştiren malzeme kompozitinin ısıl iletkenliğinde %154.9 iyileşme sağlanmıştır. Katkılanan metal oksit veya karbon tabanlı nanoparçacık bölüntüsüne bağlı olarak erime/katılaşma sıcaklıklarında önemli bir değişim olmadığı (<1.5 oC) buna karşın gizli ısılarda %20’ye varan bir azalma olduğu gözlemlenmiştir. Buna karşın ZnO nanoparçacıkların gizli ısıları iyileştirmek gibi bir etkisinin olduğu tespit edilmiştir. GNP katkılanan faz değiştiren malzemelerin ısıl iletkenliklerinde elde edilen iyileşmelerin yanı sıra uzun dönem boyunca kararlılıklarını koruyabilmesi onun bir enerji depolama malzemesi olarak kullanılabileceğini göstermiştir.

Anahtar Kelimeler

• Nanoparçaçık
• Isıl iletkenlik
• Faz değiştiren malzeme
• Diferansiyel taramalı kalorimetre

DETERMINATION OF THERMAL PROPERTIES OF A82 ORGANIC PHASE CHANGE MATERIAL EMBEDDED WITH DIFFERENT TYPE NANOPARTICLES

Öz

The low thermal conductivities of organic phase-change materials must be increased so that they can be used effectively in practice. In this work, it is aimed to enhance the thermal conductivity of PCM by adding nanoparticles into PCM. The effect of used nanoparticle type, size and shape on the thermal properties such as thermal conductivity, latent heat, melting / solidification temperatures has been systematically investigated. The thermal conductivity enhancement of composites doped with carbon based nanoparticle were found to be higher than that of the composites doped with metal oxide nanoparticles. 154.9% improvement was achieved in the thermal conductivity of the phase change material composite doped with 5% GNP. It has been observed that there is no significant change in melting/ solidification temperatures (<1.5 °CC) depending on the doped metal oxide or carbon-based nanoparticles, but deterioration up to 20% in latent heat. However, ZnO nanoparticles have been found to have the effect of enhancing latent heats. In addition to the improvements achieved in the thermal conductivities of phase change materials, their stability are protected over the long term. This result show that it can be used as an energy storage material.

Anahtar Kelimeler

• Nanoparticle
• Thermal conductivity
• Phase change material
• Differential scanning calorimetry

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