Showing papers by "Thomas F. Irvine published in 1993"

Drag relationships for liquid droplets settling in a continuous liquid

Abstract: Experiments are reported in which the drag of single liquid droplets settling in a tall column of another lighter immiscible liquid are measured. The experimental data for the eight pairs of liquids that were tested covered a range of droplet Reynolds numbers from 10[sup [minus]3] to 10[sup 4]. Two regimes of droplet settling were encountered. In the first regime, the droplets remained spherical, and the drag agreed very well with established solid sphere drag models. In the second regime, the droplets became deformed and oscillated; the drag was found to depart suddenly from predictions of spherical models and to increase with increasing Reynolds number. Empirical models for the point of departure from spherical drag and the coefficient of drag in the unstable regime are derived. The broad scope of applications for such research includes the analysis of particle motion in fluids, the study of phenomena such as rainfall, boiling and aerosol decontamination, the design of condensing economizers and air pollution control equipment, as well as the design of evaporative coolers and cooling towers.

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, approxiamately 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