Powder Technology, Vol.354, 505-516, 2019
An enthalpy based discrete thermal modelling framework for particulate systems with phase change materials
The latent thermal energy storage of phase change materials (PCM) is an attractive technique to use renewable energy. Systems with PCM capsules can be found in a wide variety of applications, but PCMs are usually approximated as a continuous phase in previous studies. The current work investigates this problem from the discontinuous point of view. The main objective is to develop an enthalpy based discrete thermal formulation that can take both heat conduction and phase change transition into consideration. The computational aspect of the formulation is fully discussed. The resulting algorithm is simple and effective. Its validity is demonstrated by solving a discrete/particle version of the one-phase Stenfan problem. In addition, the equivalent thermal properties of bulk particle materials with phase change are also derived based on a simple multi-scale modelling scheme. Numerical simulations are conducted to illustrate the effectiveness of the proposed enthalpy based discrete thermal modelling (DTEM) framework. (C) 2019 Elsevier B.V. All rights reserved.
Keywords:Phase change material;Discrete thermal element method;Effective thermal conductivity;Stefan problem