Numerical Investigation of Non-Uniform Magnetic Fields Effects on Heat Transfer and Development of Melting- Solidification Processes in an Enclosure

Developing new energy storage systems using Phase Change Materials (PCMs) have been recently attracted considerable interest, since these materials during phase transition, could absorb and release energy at a constant temperature. Due to this feature, they are widely used in energy systems. In this investigation, the effects of applying nonuniform magnetic field with negative and positive gradients on the heat transfer and also on the development of solidification and melting processes of a non-electrical conductive magnetic nano-fluid as a PCM in an enclosure in the presence of different magnetic fields have been studied numerically using single phase homogenous model and control volume technique. In the present study, the enthalpy-porosity method has been used for analyzing the solidification and melting process of phase change materials enhanced with nanoparticles (in this study Fe3O4 nanoparticles have been used). The obtained results show using nanoparticles and applying magnetic fields increase the development of solidification and melting processes. Due to heat transfer through vertical walls, the effect of the magnetic field with positive and negative gradients only in the y-axis direction has been investigated. Since the magnetic field is applied only to the mushy zone, a magnetic field with a negative gradient in the vertical axis direction will have the greatest effect on the progression of the solidification and melting process so that the time of these processes will be decreased.