Investigation of latent heat storage system using graphite micro-particle enhancement

Low-temperature energy storage system (LTESS) stores the thermal energy from the sun, exhaust gases and waste heat from industries and other sources. Phase changing materials (PCM) are used as the energy storage medium for this system. The advantage of PCM is that it has higher energy storage density, with low volume. The disadvantage of PCM for using as LTESS is that the thermal conductivity of PCM is less and this requires more time period and surface area of contact, for loading and unloading of thermal energy. A solution to this problem can be incorporating graphite micro-particles in the paraffin PCM to improve its thermal conductivity. The heat transfer of LTESS is determined experimentally. Incorporating micro-particle in the PCM has improved the heat transfer of the LTESS. Maxwell-Garnett equation is used to determine the heat transfer of PCM and J-type temperature measuring probe, and sensor apparatus is used to determine the heat transfer experimentally. The encapsulation has increased the heat-retaining ability and storage time by about 40% on average for the flow rates tested.