Online measurements of surface tensions and viscosities based on the hydrodynamics of Taylor flow in a microchannel

This paper demonstrates an online measurement technique which can measure both surface tension and viscosity for confined fluids in microfluidic systems. The surface tension and viscosity are determined by monitoring the liquid film thickness deposited in a microchannel based on the hydrodynamics of Taylor flow. Measurements were carried out for pure liquids and binary aqueous liquid mixtures. The results agreed well with reference data and theoretical models. This novel method has considerable potential for measuring dynamic interfacial tension of complex mixtures. Furthermore, it offers opportunity for integrating property measurement with two-phase flow in microchannel, opening new lines of applications.