Forced-Convection Evaporation of Droplets in a High-Temperature Environment

Abstract

Theoretical and experimental investigations were carried out on the interaction of the radial flow arising from mass transfer and the forced-convection flow field around an evaporating droplet in order to elucidate the effect of mass transfer on heat transfer. The experimental study consisted of measuring the evaporation of water droplets suspended in a laminarly-flowing steam environment. The level of mass transfer was controlled by means of radiation heat transfer to the droplet from a high-temperature cylindrical zone surrounding it. A theoretical model was developed based on: (1) uniform mass efflux (2) error-distribution solution of the momentum equation (3) integral boundary-layer formulation of the energy equation The zero-mass-efflux solutions gave good agreement with previously reported correlations for O < Re <1000. Excellent agreement was found between the experimental data and the model for the high mass transfer rates investigated.