Thermal energy storage (TES) is a technology that stocks thermal energy by heating or cooling a storage medium so that the stored energy can be used at a later time for heating and cooling applications and power generation. PCM materials are one of the most efficient ways of storing thermal energy. The latent heat storage provides much higher storage density with a smaller temperature difference between storing and releasing heat. However, practical difficulties often occur in the application of the latent heat method, due to the low conductivity, the changing density and the instability of PCMs properties.
Dispersed metal oxide nanoparticles in paraffin wax might be a solution to improve latent heat thermal storage performance. Thermo-physical properties such as thermal conductivity and latent heat could be changed for different concentration of dispersed nanoparticle. In this work, melting of paraffin wax with Fe2O3 nanoparticles used in a partially heated square cavity. The geometry used is a square box of size 20mm × 20mm .The initial temperature of the Nano particle with PCM is 300 K, the hot wall side is at a constant temperature of 355 K (Tmax) and the cold wall, opposite the hot wall, is at 300 K (Tmin) in order, the other two walls are adiabatic with the help of simulation software Ansys 14.5. The melting rate by using 1% Fe2O3 reduced by 13.92% while in the case of 3% Fe2O3 melting rate is reduced by 6.67%.The highest enhancement is achieved for the enclosure filled with Ø= 1 vol% of Fe2O3 nanoparticle concentration.