Abstract
The present study has been performed for obtaining the heat transfer enhancement characteristics of the plural microencapsulated solid-liquid phase change materials (PCM) slurry having different sizes, which flows in a straight tube heated under a constant wall heat flux condition. In the turbulent flow region, the friction factor of the plural PCM slurry was found to be lower than that of pure water flow due to the drag reducing effect of the PCM slurry. The heat transfer coefficient of the plural PCMs slurry flow in the tube was increased by both effects of latent heat evolved in phase change process and micro-convection around plural microcapsules with different diameters. The experimental results revealed that the average heat transfer coefficient of the plural PCMs slurry flow was about 2∼2.8 times greater than that of a single phase of water.