Measurement of Thermophysical Property of Energy Storage System (CaCl<sub>2</sub>&#46NH<sub>3</sub> System)

Abstract

In order to measure the thermophysical properties of ammoniated salt (CaCl 2 •mNH 3 : m = 4, 8) as an energy storage system utilizing natural resources, the measurement unit was developed, and the thermophysical properties (effective thermal conductivity and thermal diffusivity) of CaCl 2 •mNH 3 and CaCl 2 •mNH 3 with heat transfer media (Ti: titanium) were measured by the any heating method. The effective thermal conductivities of CaCl 2 •4NH 3 + Ti and CaCl 2 •8NH 3 + Ti were 0.14-0.17 and 0.18-0.20 W/(m•K) in the measuring temperature range of 290-350 K, respectively, and these values were approximately 1.5-2.2 times larger than those of CaCl 2 •4NH 3 and CaCl 2 •8NH 3. The effective thermal diffusivities were 0.22-0.24 × 10 − 6 and 0.18-0.19 × 10 − 6 m 2 /sin the measuring temperature range of 290-350 K, respectively, and these values were approximately 1.3-1.5 times larger than those of CaCl 2 •4NH 3 and CaCl 2 •8NH 3. The obtained results show that the thermophysical properties have a dependence on the bulk densities and specific heats of CaCl 2 •mNH 3 and CaCl 2 •mNH 3 + Ti. It reveals that the thermophysical properties in this measurement would be the valuable design factors to develop energy and H 2 storage systems utilizing natural resources such as solar energy.