Low melt alloy blended polyalcohol as solid-solid phase change material for energy storage: an experimental study

Abstract

This paper reports the results of the experimental study conducted on the charging and discharging performance of a pentaerythritol (PE) blended with the low melt alloy (LMA) of Bi-Sn-In-Zn. The charging and discharging time, power, the efficiency of PE added with 0.5, and 1.0 wt% of LMA determined using a shell and tube type thermal energy storage system. Therminol-55 oil, a heat transfer fluid in hot and cold conditions was circulated at 2, 4, 6 LPM through the heat exchanger during the charging and discharging processes. The results indicated that charging and discharging time reduced due to the blending of LMA with PE for all volume flow rates of therminol oil. The maximum charging and discharging powers of 265.9 W and 187.0 W respectively were observed in the case of PE + 1.0% LMA corresponding to the flow rate of 6 L per minute (LPM). The efficiencies of charging and discharging showed maximum values of 82.5% and 69.0% respectively at 6 LPM. The mean value of the overall energy efficiency of the thermal energy storage system found increased from 38.3% obtained in the case of PE to 45.2% and 51.6% obtained for PE added with 0.5 wt% and 1.0 wt% of LMA respectively.