Effect of Nanofluid on the Film Boiling Behavior at Vapor Film Collapse Available to Purchase

A high-temperature stainless-steel sphere was immersed into Al₂O₃ nanofluid to investigate film boiling heat transfer and collapse of vapor film. Surface temperature is referred to the measured value of thermocouples embedded into and welded onto a surface of the sphere. A direct contact between the immersed sphere and Al₂O₃ nanofluids is quantified by the acquired electric conductivity. The Al₂O₃ nanofluid concentration is varied from 0.024 to 1.3 vol%. A film boiling heat transfer rate of Al₂O₃ nanofluid is almost the same or slightly lower than that of water. A quenching temperature rises slightly with increased the Al₂O₃ nanofluid concentrations. In both water and Al₂O₃ nanofluid, the direct contact signals between the sphere and coolant were not detected before vapor film collapse.