Thermal field and heat storage in a cyclic phase change process caused by several moving melting and solidification interfaces in the layer

The calculation procedure is employed for the study of the thermal behaviour of PCM layers, with different melting temperatures and thermo-physical properties, with boundary conditions typical of those operating on the external walls of air-conditioned buildings. This procedure allows for the determination, at different time instants of the period P = 24 h, of the position of the bi-phase interfaces present in the layer, the field of temperature and heat flux and the instantaneous energy released and stored by each interface. The numerical results reveal interesting phenomena that, for such boundary conditions and in such detail, have never been reported previously in the literature.