Preparation and characterisation of nano enhanced phase change material by adding carbon nano tubes to butyl stearate

Abstract

A nano enhanced phase change material, NEPCM, was prepared by the addition of carbon nanotubes, CNTs, to butyl stearate. This study utilised single walled nano tube, multi-walled nanotube and modified multi-walled nanotube. Several kinds of surfactants were used to stabilise nano-particles in butyl stearate. Tetramethyl ethylene diamine (TEMED) was the best surfactant for enhancing the stability time of nano-fluid. The effect of CNTs concentration on the thermal properties of base fluid was studied and it was found that for all kinds of CNTs, the highest thermal conductivity of NEPCM was observed in weight fraction of 0.03. The modified-MWCNTs have the most enhancements in the butyl stearate thermal conductivity. It was found from differential scanning calorimetry tests, that modified-MWCNTs with 2 wt.% contents have the most effect on the latent heat of fusion of the base fluid. It was also observed that the SWCNT has a considerable effect on the melting point of PCM.