Related Experiment Video
Updated: May 30, 2026

Terahertz Microfluidic Sensing Using a Parallel-plate Waveguide Sensor
Published on: August 30, 2012
The torsional waveguide viscosity probe: design and anomalous behavior
Amir Rabani1, Richard Challis, Valerie Pinfield
1Electrical Systems and Optics Division, Faculty of Engineering, University of Nottingham, Nottingham, UK. Amir.Rabani@nottingham.ac.uk
Abstract:
This paper is concerned with the design of viscosity sensors based on a torsional waveguide. The advantages of using guided wave attenuation instead of speed for viscosity estimation are established. The effects of probe material, dimensions, and operating frequency on viscosity measurement are discussed in the context of a requirement to match the measured attenuation to the range of viscosity values that are to be measured, given the constraints on measurability imposed by the overall signal and noise conditions. A prototype probe is shown to work well with Newtonian liquids but to appreciably underestimate the viscosities of polymeric oils; these anomalies are explained quantitatively on the basis of a model of intramolecular relaxation. The probe was unsuccessful when applied to slurries, and a basic explanation is given.
Related Concept Videos
Thin-Walled Hollow Shafts
Torsional Pendulum
As long as the rigid body's angular displacement is small, its oscillation can be modeled as a linear angular oscillation. The amplitude of the oscillation is an angle. The role of mass is played by the...
Bending and Torsional Moments
The reaction developed in a structural element when subjected to an external force causes the element to bend. When a structural element bends upwards, it creates compressive normal forces on the top and tensile normal forces on the bottom, resulting in a couple that determines the bending...
Standing Waves in a Cavity
Viscosity of Fluid

