Role of nano-copper in discharging performance of latent heat storage unit

The addition of nanoparticles and fin to phase change material (PCM) has been proved to be an efficient method of enhancing heat transfer. It increases the thermal conductivity of PCM and expands the heat transfer area, which significantly improves the discharge speed of latent heat storage (LHS) system. To further increase the discharge speed of the LHS system, a novel type of umbrella-like fin was designed in the present research, and nano-copper with different concentrations was added to PCM. The transient solidifying process of nano-PCM modeled and numerically simulated. From the perspective of temperature response characteristics and heat release, the effect of nanoparticle concentration on PCM solidifying was studied. The results show that the addition of nanoparticles can improve the cooling rate of PCM, especially in the area away from the fin. When the particle concentration is 5%, the solidifying time of nano-PCM is 11.1% less than that of pure PCM. But adding nanoparticles to improve the solidifying speed of PCM is achieved by reducing the released heat. When the concentration of nano-copper increased from 0% to 5%, the latent heat release reduced by 34% and the sensible heat release reduced by 24.8%.