Some suggestions for new rheometer designs I. Theory

Abstract

Considerable interest has recently been shown in new rheometer designs which make use of a steady flow to determine the complex viscosity of an elasticoviscous liquid. Here, we develop the necessary mathematical background to a number of new rheometers of this sort. The suggested measurements involve the components of the force or the components of the couple acting on one of the instrument members. Since commercial rheometers are available which make such measurements, it is anticipated that these instruments will be adapted by some experimentalists to include the new geometries suggested in this paper.