Isıl Enerji Depolama lı Yapıca Kararlı Yeni Bir Faz Değişim Malzemesi Olarak Silikafume /Polietilen Glikol (PEG) Kompoziti

Bu çalışma yapıca kararlı yeni bir faz değişim materyali olarak silikafume / polietilen glikol(PEG) kompozitinin hazırlanması, karakterize edilmesi ve ısıl enerji depolama özelliklerinin belirlenmesi üzerine amaçlanmıştır. Kompozitler PEG'insilikafume içine vakum altında emdirme yöntemiyle hazırlanmıştır. Erimiş PEG silikafume içerisinde akma davranışı göstermeden %30 oranında hapsedilebilmiştir. Üretilen kompozit faz değişim malzemesi (FDM); SEM ve FT-IR analiz teknikleri kullanılarak karakterize edilmiştir. Kompozit FDM'nin ısıl enerji depolama özellikleri DSC analizleri ile belirlenmiştir. DSC analiz sonuçları kompozit FDM'nin erime noktasının ve erime entalpisinin sırasıyla 27.70 oCve 87.09J/g olduğunu göstermiştir. Çok sayıda gerçekleştirilen ısıtma-soğutma döngüleri sonucunda kompozit FDM'lerinin kimyasal olarak kararlı ve enerji depolama özelliklerini önemli düzeyde koruduğunu göstermiştir. TG analiz sonuçları silikafumeye emdirilen PEG'in termal kararlılığının yüksek olduğunu ortaya koymuştur. Kompozit FDM'lerin ısıl iletkenliği farklı oranlarda karbon nano tüp (CNTs) ilave edilerek arttırılmıştır. Ayrıca CNTs ilavesinin kompozit FDM'nin ısıl enerji depolama ve salıverme süreleri üzerindeki etkisi araştırılmıştır.

Silicafume/Polyethylene glycol (PEG) composite as a novel form-stablephase change material for thermal energy storage

This paper is aimed to prepare, characterize, and determine thermal energy storage properties of silicafume/polyethyleneglycol(PEG) composite as a novel form-stable composite phase change material(PCM). The composite PCM was prepared by incorporating PEG in the silicafume by using vacuum impregnation method. The PEG could be retained by 30 wt% into the silicafume without the leakage of melted PEG from the composite. The composite PCM was characterized by using SEM and FT-IR analysis techniques. Thermal energy storage properties of the composite PCMs were determined by DSC analysis. DSC results showed that the melting temperature and latent heat of the composite PCMs are 27.70 oCand 87.09 J/g, respectively. Thermal cycling test was conducted to determine the thermal reliability of the composite PCM and the results showed that the composite PCM had good thermal energy storage reliability and chemical stability. TG analysis revealed that the impregnated PEG into the silicafume had good thermal stability. Thermal conductivity of the composite PCM was improved by adding carbon nanotubes (CNTs) in different mass fractions. The effect of CNTs addition on the thermal energy storage/release times of the produced composite PCM was also tested.

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