Measurement of Thermophysical Property of Energy Storage System (CaCl₂&#46NH₃ 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.