Improving the energy efficiency of a vapour compression system using a phase change material.

When heat transfer between an evaporator and the refrigerated area is unusually low (a typical example is by natural convection) and the vapour compression system is on/off regulated, adding a planar phase change material to an existing evaporator allows to improve the global efficiency. In this paper, the case of a household refrigerator is simulated as an example. Compared to the classical vapour compression system, the new design shows a significant increase of the COP, but also a limitation of the maximum refrigerating capacity transmitted to the refrigerated area. Other benefits and limits of this technology are discussed.