PCM/ graphite foam composite for thermal energy storage device

摘要

Numerical studies are proposed to predict and investigate the thermal characteristics of a thermal storage device consists of graphite foam matrix saturated with phase change material, PCM. The composite (graphite foam matrix saturated with PCM) is prepared by impregnation method under vacuum condition, and then is introduced into a cylindrical shell and tube device while it experiences its heat from an inner tube fluid. The two-dimensional numerical simulation is performed using the volume averaging technique; while the phases change process is modelled using the enthalpy porosity method. A series of numerical calculations have been done in order to analyze the influence of fluid operating conditions on the melting process of the paraffin/ graphite foam. The results are given in terms of temperature or liquid fraction time history in paraffin/ graphite foam composite, which show that the heat transfer rate of the device is effectively improved due to the high thermal conductivity of graphite foams. Therefore, paraffin/ graphite foam composite can be considered as suitable candidates for latent heat thermal energy storage device.