Mitsuyoshi Shimaoka

Boiling heat transfer during water quenching of high temperature platinum filament.

High temperature horizontal platinum filaments have been dipped into subcooled water to simulate a new rapid solidification process, and forced convectional boiling heat transfer has been examined. A vapor film first collapsed at the edges of the filament and the collapsing sites propagated towards the center at rates ranging from 0.25∼2 m/s. The propagating rate of the collapsing site increased with increasing subcooling. A minimum heat flux point did not appear clearly in the boiling curve, and a variation of the heat flux corresponded to that of the propagating rate. Epstein and Hausers expression of the convection film boiling of a sphere or cylinder could be applied for that of the filament during water quenching.