Measurement of Liquid Film Thickness in Slug Flow of Air and Viscous Liquid in a Microchannel Available to Purchase

Liquid film thickness data in slug flow in a 320 μm diameter capillary tube have been obtained and are compared with existing data and correlations. Solutions of glycerol in water at varying concentrations between 50 and 70% were injected into the capillary tube along with air, at ambient temperature. The thickness of the liquid film was measured using a laser confocal displacement sensor. Gas slug velocity data were obtained from high speed video images recorded at 40,000 frames per second. As liquid viscosity and hence capillary number was reduced, the film thickness around the gas slugs in the capillary tube decreased as expected. The liquid film thickness data were slightly underpredicted by existing correlations.