Numerical study on n-octadecane PCM melting process inside a pear-shaped finned container

This work numerically explores the melting process of a nano-enhanced phase change material (NePCM) in thermal energy storage (TES) system. The TES unit is pear-shaped and filled with n-octadecane PCM loaded with Al2O3 nanoparticles and fitted with copper fins. The heat transport governing equations are solved using the finite element method's enthalpy-porosity approach. The melting and heat transmission processes were investigated in terms of the impacts of a variety of factors, including the volume percentage of nanoparticles, the passage of time, the number and the dimensions of the fins. The findings show that the addition of nanoparticles improves the melting process of PCM. For example, adding 6% Al2O3 into PCM decreases the melting time by 12.5%. Furthermore, longer and thinner fins are advised to increase melting rate due to decreased thermal resistance enhanced heat propagation in the deeper regions of the thermal storage unit.