Generalized quantitative criteria for predicting the rate-controlling mechanism for vapor bubble growth in superheated liquids

Abstract

Criteria are presented for predicting the relative importance of the inertia of the liquid and heat transfer in the liquid as controlling effects for spherically symmetric vapor bubble growth in liquids. The coupled governing equations including both of the above effects are first cast in appropriate dimensionless forms. Then numerical solutions of the coupled equations are compared to the limiting solutions for solely liquid inertia and solely heat transfer controlled growth processes, in order to determine the respective regions of importance of these two mechanisms. The cases of growth initiated by a step decrease and a linear decrease in system pressure are both considered. The criteria are developed for the case of an idealized fluid having a constant vapor density and a linear vapor pressure curve, and then shown to be approximately independent of the vapor density and pressure relations of the particular fluid. The applicability and usefulness of the criteria are supported and illustrated by comparison of predictions based on them with previous theoretical and experimental results taken from the literature.