PHASE-CHANGE MATERIAL ENERGY-STORAGE SYSTEM EMPLOYING PALMITIC ACID

Experimental investigation of palmitic acid as a phase change material (PCM) for energy storage has been carried out in this work. The parametric study of phase transition included transition times and temperature ranges, propagation of the solid liquid interface. as well as the heat flow rate characteristics of the employed circular tube storage system. The experimental results proved that the melting front moves in the radial as well as in the axial directions. The convection heat transfer in the liquid phase plays an important role in the melting process. And the simple conduction model does not describe the melting process properly. The flow rate, of the heat transfer fluid in the experimented range, has insignificant effect on the transition process. The melting time can be reduced significantly by placing the tube containing the PCM in a horizontal position rather than in a vertical one. The dimensionless phase transition time is related to Stefan number by a simple correlation.