- De Lucia, M. and Bejan, A., Thermodynamics of phase-change energy storage. The effects of liquid superheating during melting, and irreversibility during solidification,
Journal of Solar Energy Engineering, Transactions of the ASME, vol. 113 no. 1
pp. 2 - 10 .
(last updated on 2007/04/08)
This paper considers the question of whether the optimum phase-change temperature for maximum exergy storage is universally equal to the geometric mean of the heat source and environment temperature, Tm = (T infinityTe)½. The study consists of three parts. The first deals with the conduction-melting process, and shows that the optimum melting temperature is generally greater than the geometric mean of the source and environment temperatures. The second part covers the conduction-solification process, and concludes that the irreversibility of solidification decreases monotonically as the phase-change temperature increases. The third part treats the complete cycle of melting (storage) followed by solidification (retrieval), and demonstrates that the optimum phase-change temperature is greater than the optimum temperature of the melting process alone.
Heat Transfer - Phase Transitions;Mathematical Models;