Enhanced solidification/melting heat transfer process by multiple copper metal foam for ice thermal energy storage

Abstract

In this work, water embedded in Copper Metal Foam (CMF) to enhance ice thermal energy storage performance was comprehensively studied theoretically and experimentally. The effects of filling ratio, specification and specification arrangement of CMF on heat transfer characteristics during the solidification/melting process were analyzed. The results showed that the cold storage/release rate and comprehensive heat transfer coefficient increased as the filling ratio increased from 0 to 6.6 %, whereas the thermal cycle time, supercooling and cold storage/release capacity decreased. More importantly, the heat conduction increased from 67.72 to 91.22 % as the filling ratio increased from 3.2 to 6.6 %, which indicates that heat conduction is dominated for high filling ratio. Furthermore, the thermal conductivity increased with the decreased in porosity or increased in pore density, and the influence of pore density was less than that of porosity. It is concluded that specification arrangement could improve the performance of non-uniform solidification/melting process by arranging CMF with the higher thermal conductivity at the location possessing larger thermal resistance. As a result, specification arrangement CMF has a better performance with 21.7 % shortened thermal cycle time, 25.1 % increased average rate and only 0.7 % decreased capacity than non-arrangement due to the increased uniformity of the temperature distribution.