Effect on solidification of deionized water based PCM in a spherical encapsulation- An experimental study

An aim of project work is to investigate the effect on solidification of phase change material (PCM) in a spherical capsule for cool thermal storage applications. The PCM used as Deionized (DI) water and low-density polyethylene (LDPE) spherical capsule is used as an encapsulation material. It is filled with three different concentration of PCM with NaCl of 0.5, 1.0 and 1.5 wt., % of total volume of encapsulation. An experiments are conducted by immersing the spherical capsules in the constant temperature bath which is maintained at -7 degrees C temperature for all samples. The solidification time is observed in each capsule at various radial locations which correspond to 50%, 75%, and 100% of the mass solidified. The results obtained reveal that the PCM of NaCl has a great influence in reducing the solidification duration. Further, the capsule with 0.5wt.%, shows better results till the solidification of 75% mass than all the other capsules and slows down thereafter. Hence it is concluded that the consideration of DI water with 0.5wt.%, mass of NaCl in the spherical capsule for the design of the energy storage would increase energy efficiency of the system and reduce the energy consumption the chiller.