THE EFFECT OF SURFACE GAS INJECTION ON FILM BOILING HEAT-TRANSFER

A database was developed for heat transfer from a horizontal plate wit h film boiling and gas jetting occurring simultaneously, in a pool of water maintained at its saturation temperature. The effect of passing nitrogen through established film boiling is to increase the heat tran sfer from that surface. At the highest measured superficial gas veloci ty, approximately 8.5 cm/s, and for a constant surface temperature, th e heat transfer increases by a factor of two over the heat transfer wi th no enhancement by gas flux. Further, as the superficial gas velocit y approaches zero, the data approach the stable film boiling asymptote . A model was developed to correlate the database. The result is an eq uation that represents better than 90 percent of all the measured data within +/- 15 percent bounds.