The impact of employing a magnetic field as well as Fe₃O₄ nanoparticles on the performance of phase change materials

In this study a 2D cubic chamber model filled with paraffin is analyzed with and without the inclusion of magnetic Fe₃O₄ nanoparticles at concentrations of 0.5, 1, 1.5 and 2 wt%, and an external magnetic field of intensities 0.005, 0.01, 0.015 and 0.02 T. It is ascertained that adding magnetic nanoparticles leads the horizontal temperature gradient to be reduced owing to increments in thermal conductivity. Additionally, this feature is found to be accelerated by applying an external magnetic field, which shapes highly conductive cluster formations of nanoparticles. However, since the increase in nanoparticle concentration and magnetic intensity increases the composite viscosity, there is an optimum configuration while applying both schemes. As such, the addition of 1 wt% nanoparticles provides the best results, as the melting time is reduced up to 25% compared to pure paraffin. Meanwhile, the melting time of a 1 wt% nanoparticle-containing phase change material (PCM) in the presence of an external magnetic field is improved up to 24% compared to the case with no external magnetic field. Also, the heat transfer coefficient of a 1 wt% nanoparticle-containing PCM both with and without an external magnetic field is also staggeringly enhanced compared to pure paraffin. Good correspondence with experimental data was achieved.