Boiling Phenomenon of Graphene Nano-Coating Wick Heat Pipe

Experiment of nano-capillary boiling phenomenon of graphene nano-based heat pipe on water as working fluids have been carried out. The coating process is carried out by performing an electrophoretic deposition process using graphene nanofluid. Graphene nanofluid was made by heating and stirring for 15 minutes in a solution consisting of graphene and distilled water with a fraction volume of 1%, then followed by an EPD process by dipping a copper pipe into a nanofluid which was given a platinum anode and 23 volt of electricity for 15 seconds. Boiling phenomena can be observed from the results of data retrieval through high-speed visualization cameras while observing thermal performance through temperature data retrieval. Based on the results obtained, the nanocoated heat pipe thermal performance is better than the uncoated heat pipe. The nanocoated heat pipe could handle higher heat flux as shown by the boiling curve at lower temperature difference between heat pipe surface and the saturated water, higher heat transfer coefficient about 215% than the uncoated heat pipe which indicates that the heat transfer phenomena occurred in nanocoated heat pipe is better than uncoated heat pipe. The bubble diameter that formed in the boiling process of nanocoated heat pipe is smaller and released faster than the uncoated heat pipe.