Melting of nano-PCM in an enclosed space: Scale analysis and heatline tracking

Nanoparticle enhanced phase change material (or nano-PCM) is an attractive option to enhance the performance of thermal energy storage systems (e.g., solar-thermal energy storage system). In this study, authors have investigated the melting performance of nano-PCMs inside a square enclosure which is a representative geometry of a thermal energy storage system. Three PCMs with different melting temperatures were experimented: (i) paraffin wax (Tm=54°C>T∞), (ii) coconut oil (Tm=24°C≈T∞), and (iii) Rubitherm® RT-18 (Tm=18°C