Experimental study on thermal storage and heat transfer performance of microencapsulated phase-change material slurry

Microencapsulated phase change material (MPCM) slurry has received attention due to their higher thermal storage density, was introduced as a storage medium in latent thermal energy storage (LTES) system. Based on this background, this article presented the experimental results of the thermal storage and heat transfer characteristics of MPCM slurry during cooling discharging process, a series of experiments were carried out by controlling variable. Hexadecane (C16H34) and urea-formaldehyde was used as the core and shell of PCM to form MPCM with core-shell ratio of 7:3 by weight. The temperature evolutions of the MPCM slurry were obtained during the experiment, and the volumetric thermal storage capacity, cooling discharging rate were calculated under different stirring rates and heat transfer fluid (HTF) initial inlet temperatures. From the experimental results, it is estimated that the thermal storage and heat transfer performance of MPCM slurry both were enhanced remarkably by phase change. In addition, accelerating the stirring rate of stirrer can enhance the thermal storage capacity. At 300 rpm, the volumetric thermal storage capacity and mean discharging rate are about 1.28 times higher than that of MPCM slurry without stirring. At the same stirring rate, the mean discharging rate of 20 degrees C is 1.24 times higher than that of 10 degrees C.