Nucleate-boiling type evaporation of binary-liquid drops on heated surfaces

Abstract

A binary-liquid drop evaporates on a heated surface in the nucleate-boiling type vaporization regime taking into account the effect of drop geometry. A maximal slowing down of drop evaporation is disclosed together with the occurence of a minimum surface-drop heat flux at different concentrations of the more volatile component. These phenomena are observed both theoretically and experimentally. Since the nucleate-boiling vaporization regime gives a minimum drop lifetime resulting in quicker vaporization (i.e. the best operating condition) and the rate of vapor formation together with air motion controls the combustion rate, the disclosure may be of some use in application to the regulation of the combustion rate in compression-ignition engines and oil-fired appliances.