| Title |
Enhancement of Pool Boiling Heat Transfer Coefficients withthe Use of Carbon Nanotubes |
| Keywords |
Pool boiling heat transfer ; 비등 열전달 ; Heat transfer coefficients ; 열전달계수 ; Carbon nanotubes ; CNTs, 탄소나노튜브 |
| Abstract |
In this study, the effect of carbon nanotubes(CNTs) on boiling heat transfer is investigated. Three refrigerants of R22, R123, R134a, and water are used as base working fluids and 1% of CNTs by volume is added to the base fluids to study the effect of CNTs. All data are obtained at the pool temperature of 7℃ for all refrigerants and 100℃ for water in the heat flux range of 10∼80kW/m2. Test results show that CNTs increase the boiling heat transfer coefficients for all fluids. Especially, large enhancement was observed at low heat fluxes. With increasing heat flux, however, the enhancement was suppressed due to vigorous bubble generations. Fouling was not observed during the course of this study. Optimum quantity and type of CNTs and their dispersion should be examined for their application in pool boiling heat transfer. |