Energy storage with PCMs: Experimental analysis of paraffin's phase change phenomenon & improvement of its properties

Using organic materials is one of the most efficient ways of storing thermal energy. the latent heat storage provides much higher storage density with a smaller temperature difference between storing and releasing heat. however,it's noted that slow thermal response is due to low thermal conductivity of pcms. this paper presents relevant previous methods for improving the thermal conductivity of the used pcm,particularly paraffin,to effectively charge and discharge latent heat energy and looks at the formulation of the phase change problem. furthermore,experiences to improve the solid-liquid phase change process were conducted to investigate a technique of enhancing the thermal conductivity of paraffin by incorporating in it a 1% mass fraction of two additives (aluminum and copper). the energy was stored in paraffin and was discharged to cold water. charging and discharging processes were performed and experimental results showed that incorporation of the additives improves heat transfer capabilities. charging time was reduced and useful heat gain increased by adding aluminum powder.