Paper Title
Effect of a Heat Transfer Surface in The Flow Boiling System Using Ographene Nanofluid

When nanofluids are used in the heat transfer system, nano-fouling phenomena can take place on the heat transfer surface due to deposition of the nanoparticles. But it is lacked of study on effect of efficiency and safety in the system. Therefore, this work experimentally explored the influence of nano-fouling, and it was also compared and analyzed CHF, flow boiling heat transfer coefficient, contact angle, and surface roughness. The working fluids in this study were used as purewater and a 0.01 vol% oxidized graphene nanofluid. The flow velocity conditions are established at 0.5, 1.0, and 1.5 m/s. Also, the nanoparticles of oxidized graphene were deposited on a heat transfer surface, and artificial spray coating times for nano-fouling are established at 0, 120, 180, and 240 sec. As the results, it was found that the superheated temperature to the CHF extremely increased in case of nano-fouling, it is caused by physical damage of heat transfer system. Also, the contact angle decreased when the flow velocity and nano-fouling were increased. Keywords: Graphene, Nanofluid, Flow boiling heat transfer, Critical heat flux, Fouling.