Numerical Study of PCM-Based Energy Storage System Using Finite Difference Method

Abstract

Energy storage systems incorporating phase change material (PCM) are becoming the answer to intermittent energy availability in the area of solar cooking vessels and solar room heating systems. These thermal energy storage systems are efficient, reliable and can reduce running costs and investments. The present work investigates the melting of n-octadecane using enthalpy formulation method by using finite difference method-based discretization. Accordingly, a numerical model is developed in MATLAB which is validated first by comparing with previous works. Further using the developed model studies on wall materials, thickness, different PCMs and temperatures are carried out. It is found that metal containers with higher thermal conductivities provided significant boost in energy storage. The increased thickness of walls adds significant change only if containers are of lower thermal conductivity such as steel. Different PCMs are analysed, and their operating temperature and energy storage capabilities are studied. In addition, enthalpy equation in cylindrical coordinates is solved since practical PCM storages are commonly cylindrical in shape. At the end, the numerical results are compared with an experimental case with paraffin wax as PCM. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd 2024.