The Effect of Surface Gas Injection on Film Boiling Heat Transfer

Abstract

A database was developed for heat transfer from a horizontal plate with 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 transfer from that surface. At the highest measured superficial gas velocity, approximately 8.5 cm/s, and for a constant surface temperature, the heat transfer increases by a factor of two over the heat transfer with no enhancement by gas flux. Further, as the superficial gas velocity approaches zero, the data approach the stable film boiling asymptote. A model was developed to correlate the database. The result is an equation that represents better than 90 percent of all the measured data within ±15 percent bounds.