Sonosynthesis of Des/Cnt Nanofluid – Stability and Thermal Conductivity Studies
Carbon nanotube (CNT) nanofluids have demonstrated high thermal enhancement due to its outstanding thermal conductivity and high aspect ratio. The next challenge which is limiting the enhancement of heat transfer is the high vapor pressure, corrosion and low thermal stability of the conventional base fluid used in water based nanofluids. Thus, new type of base fluid known as Deep eutectic solvents (DES) are proposed in this research as a potential substitute for the conventional base fluid to form CNT nanofluids. Choline chloride, ethylene glycol and triethylene glycol are used to synthesize DES wherein CNT is dispersed into the DES using water bath sonicator. The stability of CNT nanofluids was studied via visual observation and UV-Vis spectrophotometer. The suspended particle size distribution was measured using the NanoSightinstrument while the thermal conductivity was measured using thermal property analyzer. The synthesised nanofluid was stable in EG based DES for 1 day and 3 days in TEG based DES. Thermal enhancement of 30% was measured in EG based DES-CNT nanofluid whereas negative thermal enhancement were observed in TEG based DES-CNT nanofluid.
Keywords— Deep Eutectic Solvents, Carbon Nanotube, Stability, Thermal Conductivity, Choline-Chloride, Glycol.