Measurement of viscosity using wave mode conversion

This paper presents a novel cell to measure the dynamic viscosity of liquids using ultrasound and wave mode conversion. The cell uses the complex reflection coefficient of shear waves at a solid-liquid interface. The transmitted and reflected waves are measured by a large aperture PVDF membrane. The magnitude and phase of the coefficient are obtained by normalizing the signal from the solid-liquid interface with respect to the one from the solid-air interface in the frequency domain. Measurements of the viscosity of glycerol and honey were made in the range from 1.5 to 14 MHz. The experimental results were compared with those from a rotational viscometer