Void fraction predictive methods in two-phase flow across a small diameter channel

Abstract

Predicting gas void fraction during two-phase flow in channels is a very important aspect of engineering calculations when designing process apparatus. There is a number of well known methods in the literature for calculating gas void fraction developed for two-phase flow in conventional channels. Unfortunately, there are still no of methods for calculating gas void fraction that would be applicable to two-phase flow in mini-channels. Due to the above, the paper attempts to evaluate methods for calculating gas void fraction for two-phase flow presented in literature: gas-liquid and vapour-liquid in channels of small diameter. To that end, calculation results were compared with 83 sets of experimental data for air-water flow and 171 sets for vapour-liquid flow (R717 and R744). The analysis which was carried out allowed us to select the most accurate calculation methods that can be successfully applied for calculations of gas void fraction in two-phase flow in small diameter channels.