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arXiv · 1902.04758

Steady streaming viscometry of Newtonian liquids in microfluidic devices

Giridar Vishwanathan·Gabriel Juarez
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Abstract

We report a novel technique capable of measuring the kinematic shear viscosity of Newtonian liquids with steady streaming in microfluidic devices. This probe-free microrheological method utilizes sub-kilohertz liquid oscillation frequencies around a cylindrical obstacle, ensuring that the inner streaming layer is comparable in size to the cylinder radius. To calibrate the viscometer, the evolution of the inner streaming layer as a function of oscillation frequency for a liquid of known viscosity is characterized using standard particle tracking techniques. Once calibrated, we show how the steady streaming viscometer can be used to measure low-viscosity liquids and volatile liquids.

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Giridar Vishwanathan, Gabriel Juarez. 2019-02-13. Steady streaming viscometry of Newtonian liquids in microfluidic devices. https://doi.org/10.1063/1.5092634

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