THERMAL CONDUCTIVITY ENHANCEMENT OF PHASE CHANGE MATERIALS USING NANOMATERIALS FOR PASSIVE COOLING

Abstract

In terms of the world’s energy consumption, and greenhouse gas (GHG) emissions, buildings contribute 41% and 30% respectively. Additionally, in countries with tropical climates, the demand for cooling increases as global warming is on the rise. As such, it is essential to look at solutions which can bring down the cooling load of a building so that GHG emissions do not continue to increase. In recent years, huge emphasis has been placed on Phase Change Materials (PCMs) as a material used for Thermal Energy Storage (TES). However, the issue with PCM is that it faces low thermal conductivity which impedes its ability to be used as a material for TES. As such, different enhancers have been researched and studied on to increase the thermal conductivity of PCMs. These include using porous matrices, nanomaterials and biochar where in this paper, it is found that aluminium honeycomb has led to the highest thermal enhancement of 112.6% where thermal conductivity increased from 0.2398 W/mK to 0.5098 W/mK. A thermal enhancement of 26.32% was observed when Multi-walled Carbon Nanotubes (MWCNT) were used and the highest thermal enhancement for the biochar was black carbon where it obtained a thermal enhancement of 6.65%. Limitations, recommendations and future outlook will also be discussed at the end of this paper.