Testing and analysis of a dual-tube latent heat storage system

Abstract

In order to effectively charge and discharge a latent heat thermal energy storage (LH-TES), a driving temperature difference between charging and discharging needs to exist, resulting in a higher charging than discharging temperature. A dual-tube LH-TES concept was developed in order to make this possible using different media or process parameters in separated tubes without the need for expensive valves and control systems. A storage unit was designed, tested and built using two different refrigerants in the respective charging and discharging processes, showing the feasibility of such a system. An axially finned tube was designed to be assembled on tubepairs, allowing for heat conduction via highly conductive aluminum directly between the circuits, as well as heat transfer between the heat transfer fluid and the phase change storage material. Data from the experimental analysis will be shown and discussed