Experimental evaluation of the melting behaviours of paraffin within a hemicylindrical storage cell.

Phase change materials (PCM) have been widely used as latent energy storage media due to their useful high energy density with small storage volume at nearly constant temperatures throughout solidification and melting. In this paper, experimental evaluation of the melting of a paraffin wax (RT58) PCM inside a hemicylindrical storage cell is outlined. The cell is heated on its straight vertical wall by means of flowing hot water, while the curved side of the cell is thermally insulated. The temperatures of the PCM at various locations are measured using thermocouples, while a digital camera is used to visualise the melting process. A set of experiments is performed to examine the influence of variation of hot water temperature on various melting characteristics including the temperature field of the PCM, the progress of the melting front, the melt fraction, the stored energy, and the Nusselt number. The experimental findings reveal that increasing hot water temperature leads to a reduction of melting time and increases in the stored energy and the Nusselt number. The melting process is expedited by 15.4 and 16.5% when the temperature of hot water increases from 80 °C to 85 °C, and from 85 °C to 90 °C, respectively. [ABSTRACT FROM AUTHOR]