Analyzing thermal characteristics of an inorganic phase change material

Abstract

The use of inorganic phase changing materials (PCMs) in thermal energy stowage systems has become widespread due to the remarkable energy saving capabilities of these substances. In the current investigation, the enhancement in energy stowage capability of the calcium chloride hexahydrate (CaCl2·6H2O) had been attempted with the assistance of nano-silica addition. Four different proportion of nano-silica (0.3%, 0.6%, 0.9% and 1.2%) had been employed for this purpose. The thermal characteristics namely, latent content, phase transformation temperatures, and thermal conductivity of the CaCl2·6H2O with the presence of nano-silica had been assessed using DSC and thermal properties analyzer. The results confirmed that the inclusion of nano-silica at 0.6% mass proportion in CaCl2·6H2O would enhance the thermal stowage characteristics in terms of its thermal conductivity to a grander magnitude, without much losing the latent content of the salt hydrate. Whereas, the maximum drop in latent content of 27.1% and 27.51% during heating and cooling was observed at 1.2% fraction of nano-silica in CaCl2·6H2O.