Numerical analysis of the discharging performance of a solar energy storage tank containing PCM modules

doi:10.3969/j.issn.2095-4239.2013.04.006

Abstract

Abstract: Numerical simulations were carried out on the discharging behaviour of a thermal energy storage water tank containing PCM modules and a tank containing only water. The modeling was done by using a CFD software package FLUENT. The results show that the cold inlet water can be heated by the PCM module during the discharging process and the PCM modules also act as a diffuser to reduce the disturbance caused by the inlet cold water. The PCM modules improve the thermal stratification of water during the discharging process. At a flow rate of 5 L/min, the discharging efficiency of the tank with PCM modules is 7% higher than that of the normal tank and the discharging efficiency of the water tank with PCM modules decreases with increasing water flow rate.

Key words: latent energy storage, PCM, numerical simulation, discharging efficiency

CLC Number:

TK02

ZHANG Yongxin, LI Shuhong, CAO Kai, LI Xianliang, GU Weiwei. Numerical analysis of the discharging performance of a solar energy storage tank containing PCM modules[J]. Energy Storage Science and Technology, 2013, 2(4): 377-382.

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