Abstract
This paper investigates critical heat flux (CHF) in saturated pool boiling for water and nanofluid on a 7 mm diameter vertical copper surface at pressures 0.1 to 0.8MPa. The nanofluid was prepared by dispersing TiO_2 nanoparticles with the concentration of 0.002wt% in deionized water. The CHF of the nanofluid was enhanced 2.4 times the CHF in water boiling at atmospheric pressure. With increasing pressure, however, the CHF enhancement effect by the nanofluid is decreased, and disappeared at pressures higher than 0.6MPa. It was also found that the well-known CHF correlations by Zuber and Lienhard predict considerably smaller CHF values than the present data for water boiling at high pressures.
