Performance evaluation of a solar thermal energy storage system using nanoparticle-enhanced phase change material

• Published in: International journal of hydrogen energy 2019-01, Vol.44 (3), p.2013-2028
• Main Authors: Elbahjaoui, Radouane, El Qarnia, Hamid
• Format: Article
• Language: English
• Subjects: Heat transfer fluid (HTF); Latent heat storage unit (LHSU); Melting; Nanoparticle-enhanced phase change material (NPCM); Solar energy storage
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2018.11.116

This paper presents a numerical investigation on the thermal performance of a solar latent heat storage unit composed of rectangular slabs combined with a flat-plate solar collector. The rectangular slabs of the storage unit are vertically arranged and filled with phase change material (PCM: RT50) dispersed with high conductive nanoparticles (Al2O3). A heat transfer fluid (HTF: water) goes flow in the solar collector and receives solar thermal energy form the absorber area, then circulates between the slabs to transfer heat by forced convection to nanoparticle-enhanced phase change material (NEPCM). A numerical model based on the finite volume method and the conservation equations was developed to model the heat transfer and flow processes in the storage unit. The developed model was validated by comparing the obtained results with the experimental, numerical and theoretical results published in the literature. The thermal performance of the investigated latent heat storage unit combined with the solar collector was evaluated under the meteorological data of a representative day of the month of July in Marrakesh city, Morocco. The effect of the dispersion of high conductive nanoparticles on the thermal behavior and storage performance was also evaluated and compared with the case of base PCM without additives. •A solar thermal energy storage system using NEPCM is numerically investigated.•The storage system consists of NEPCM slabs coupled with a solar collector.•Natural convection within NEPCM affects the morphology of the melting front.•NEPCM enhances the melting rate and the collection efficiency.•NEPCM increases the sensible storage efficiency of the storage unit.