Measurement of Thermophysical Property of Energy Storage System (CaCl₂.NH₃ System)

Yuki Sakamoto^1*, Hideki Yamamoto²

¹Faculty of Informatics, Naragakuen University, Nara, Japan.
²Faculty of Environmental and Urban Engineering, Kansai University, Suita, Japan.

DOI: 10.4236/nr.2014.512060                

Abstract

In order to measure the thermophysical properties of ammoniated salt (CaCl₂^.mNH₃: 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 CaCl₂^.mNH₃ and CaCl₂^.mNH₃ with heat transfer media (Ti: titanium) were measured by the any heating method. The effective thermal conductivities of CaCl₂^.4NH₃ + Ti and CaCl₂^.8NH₃ + 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 CaCl₂^.4NH₃ and CaCl₂^.8NH₃. The effective thermal diffusivities were 0.22 - 0.24 × 10^-6 and 0.18 - 0.19 × 10^-6 m²/sin the measuring temperature range of 290 - 350 K, respectively, and these values were approximately 1.3 - 1.5 times larger than those of CaCl₂^.4NH₃ and CaCl₂^.8NH₃. The obtained results show that the thermophysical properties have a dependence on the bulk densities and specific heats of CaCl₂^.mNH₃ and CaCl₂^.mNH₃ + Ti. It reveals that the thermophysical properties in this measurement would be the valuable design factors to develop energy and H₂ storage systems utilizing natural resources such as solar energy.

Keywords

Energy Storage System, Thermophysical Property, Calcium Chloride (CaCl₂), Ammonia (NH₃), Ammoniated Salt, Ammoniation, Heat Transfer Media

Conflicts of Interest

The authors declare no conflicts of interest.

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