A Comparison Study on the Heat Transfer Behavior of Aqueous Suspensions of Rod Shaped Carbon Nanotubes with Commercial Carbon Nanotubes

摘要

The heat transfer behavior of three aqueous suspensions of rod shaped carbon nanotubes namely NC300, NC200 and a commercial carbon nanotube (CNT) were studied. The nanocarbons were employed with the presence of sodium dodecyl sulphate (SDS) and deionized water to prepare nanofluid. Series of nanofluids were formulated using 0.6% weight ratio of nanocarbon with additional of 0.24% of SDS and deionized water. The nanofluids were then homogenized and ultrasonicated to obtain optimum stability. Morphology of nanocarbon and nanofluid suspension was analyzed using Scanning Electron Microscopy (SEM) analysis and Optical Metallurgical Microscope. Thermal conductivity was then evaluated at 6°C, 25°C and 45°C and heat transfer coefficient was measured by using a custom made heat transfer test rig. A significant enhancement of thermal conductivity was recorded in all the three aqueous suspensions while an enhancement in the heat transfer coefficient was observed only in NC300.