Performance evaluation of latent heat TES system-case study: Dimensions improvements of annular fins exchanger

Abstract

Thermal Energy Storage (TES) is an important challenge for the development and implementation of Concentrated Solar Power (CSP) plants. The heat can be stored in a sensible, thermochemical or latent form. Recently, the latent heat thermal energy storage (LHTES) kind has gained the most of research interest as it has the advantage of increasing the energy density of the current commercial TES systems through the use of a Phase Change Materials (PCM). However, the main limitation of PCMs technology is the low thermal conductivity, which affects the system performances and lead to significant energy losses. In this sense, a good container design can impact positively the system performances. For that sake, several designs have been proposed to overcome the decreasing heat transfer rate. For this purpose, this study propose many enhancements and improvements of the fins method based on the integration of PCM in an exchanger with annular fins. The main objective of this paper is to study the impact of finned exchangers on the total flow transferred and also on the height of these annular fins. Finally, the physical model describing the thermal behavior of the studied system is developed and simulated after 80 min of charging process. Keywords: Annular fins, Exchanger fins, Latent heat thermal energy storage, Phase change material, Thermal conductivity, Length of the fins