Enhancement of phase change along the long tubes of a latent heat storage unit

Abstract

This paper presents the results of an experimental study on the solidification along a long horizontal tube submersed in liquid phase change material (PCM) and the enhancements due to the use of a turbulence promoter. The experimental rig consists of a long copper tube fixed coaxially inside a larger PVC tube filled with liquid PCM (water). The working fluid at a temperature lower than the PCM phase change temperature flows inside the copper tube provoking the solidification of PCM over its surface. The PVC tube is fitted with three windows along its length for observation and photographing the solidified PCM interface. The tests were realized for values of Reynolds number from 741 to 2280 and temperatures varying from -5 to -20 ° C with and without turbulence promoter showed their effects on the interface position, the solidification velocity and how they were enhanced because of the turbulence promoter.