Real Time Solar and Controlled Experimental Investigation of a Latent Heat Energy Storage System

Abstract

An experimental characterization of a latent heat energy storage system (LHESS) with dodecanoic acid as the phase change material was conducted under real-time solar and controlled experimental conditions. During charging it was found that natural convection played a significant role, while discharging was mainly dominated by conduction. The heat transfer fluid (HTF) inlet temperature affected the overall performance more significantly than the HTF flow rate. Seasonal evaluation showed that insufficient melting during short days interrupted the onset of natural convection. A comparison between latent and sensible storage showed that the helical coil heat exchanger is not as effective with PCM in comparison with water due to heat transfer limitations. Finned tubes were compared to the helical coil heat exchanger and showed improved performance during charging and discharging. A Fourier number based design method was proposed and validated, which could serve as a useful technique for future designs of LHESS.