A PCM/Forced Convection Conjugate Transient Analysis of Energy Storage Systems With Annular and Countercurrent Flows

Abstract

Latent heat energy storage systems with both annular and countercurrent flows are modeled numerically. The change of phase of the phase-change material (PCM) and the transient forced convective heat transfer for the transfer fluid are solved simultaneously as a conjugate problem. A parametric study and a system optimization are conducted. It is found that the energy storage system with the counter-current flow is an efficient way to absorb heat energy in a short period for pulsed power load space applications.

Numerical analysis of water melting and solidification in the interior of tubes

“…The latter is one of the first experimental and numerical studies on phase change that employ water as the PCM. Another investigation worth mentioning is that of "Cao et al (1991) …”

Analysis of Freezing in an Eccentric Annulus

“…The experimental results for unfixed melting and solidification showed that the addition of an inner tube can significantly accelerate the phase-change process. Cao et al (1991) studied the twodimensional change of phase in a PCM cylinder and a PCM concentric annulus conjugated with the forced convection of the transfer fluid. The temperature of the transfer fluid varied along the axial direction instead remaining a constant.…”

“…The latent heat thermal energy storage system in Betzel and Beer (1988) and Cao et al (1991) are modeled as two concentric annular tubes in which the inner tube and the outer tube have the same center. However, eccentricity can exist in some latent heat energy storage systems due to manufacturing error and for special application requirements.…”

Experimental and numerical investigation of thermal energy storage with a finned tube

“…One of them is the shell-and-tube-type heat exchanger with the phase change material placed in the shell, and the heat transfer fluid flowing through the tubes. Studies related to this configuration are done by Ismail and Alves (1986), Cao and Faghri (1991a), Cao and Faghri (1991b), Zhang and Faghri (1996a), Bellecci and Conti (1993), and Lacroix (1993). The second configuration is a rigid capsule in which the phase change material has been placed, and the heat transfer material flows through a tube surrounding the capsule.…”

“…Using the enthalpy model, the problem of storing energy in a shell-and-tube type unit was also solved by Bellecci and Conti (1993). Cao and Faghri (1991a) studied the latent heat energy storage systems for both annular and countercurrent flows and numerically determined that the storage system with the countercurrent flow was an efficient way to absorb heat energy.…”