Parallel plate channels for latent heat thermal energy storages

Abstract

Lately TES systems for thermal applications, such as space and water heating, air-conditioning, cooling, etc. have received much attention. In TES system, energy is stored by changing the temperature of a storage medium or employing the latent heat of Phase Change Material (PCM). For a TES system, it is important to have a charging velocity rather high, because for an assigned system size, it is possible to obtain greater amount of stored energy in less time. Therefore, the heat transfer between the working fluid and the TES system should be improved by increasing the surface exchange area. In the present work a computational investigation on thermal energy storage system using Phase Change Material (PCM) is accomplished. The system is a set of different parallel plates, half of them are filled with PCM and in the others the working fluid, air, flows. Various configurations for different channels per unit of length (CPL) are investigated. A comparison between a direct model and a porous medium model is carried out. The porous medium is modeled with the Darcy-Forchheimer law. Numerical simulations are carried out using the Ansys-Fluent code for the direct model with 2n channels for direct and equivalent porous medium.