Solidification characteristics of deionized water in a spherical capsule using bio-additives: An experimental study

Abstract The present work investigates the solidification activity of deionized water as phase change material dispersed with various bio-additives such as gelatin and corn starch in a spherical capsule immersed in a constant temperature bath. Tests are carried out at two different bath temperatures (-6°C and -9°C) and it was noted that deionized water undergoes a subcooling of -3.8°C at a bath temperature of -6°C. However, no subcooling is reported for the deionized water with a concentration of 0.1wt.% for both the additives. A maximum reduction of 51% and 45% in total solidification time is observed for gelatin solution at bath temperatures of -6°C and -9°C respectively. A significant reduction of 82% is observed while considering 50% of phase change material(PCM) mass at a bath temperature of -6°C. Hence, it is concluded that reducing subcooling and partial charging of water-based PCMs would help to increase the Cool Thermal Energy Storage (CTES) system’s energy efficiency.