Numerical study of heat transfer inside a Keeping Warm System (KWS) incorporating phase change material

We present in this work an enhanced insulated container using phase change material (PCM) solidification process as a Keeping Warm System (KWS). A square enclosure with one vertical PCM wall whereas the other one kept at ambient temperature has been taken as a simplified configuration of the KWS. The solidification of the PCM releases latent heat inducing a natural convection air flow inside the cavity and compensating the heat loss through the cold wall. A transient, two-dimensional numerical model has been developed to study the coupled heat transfer in the PCM and air inside the enclosure. The results show the effect of the PCM on the time wise variations of the gas average temperature and the Nusselt number at both cold and hot sides of the cavity. The comparison with the case without latent heat shows that the heat retention in the cavity has been significantly enhanced by the presence of a PCM wall.