Foundations of extensional viscometry part II: Essentials as to design and analysis of hose viscometers

Abstract

After a historical survey on the evolution of extensional viscometry, two novel types of extensional viscometers are proposed under the designations closed-end and open-end hose viscometer. The hose, which forms an elastically extensible cover of a prolate circular cylinder shape, is to hold an incompressible fluid specimen for investigation, especially under forced oscillations. The measurement of the first type concerns the axial force of the specimen in a thin-walled hose; the measurement of the second type concerns the radial traction of the specimen in a thick-walled hose. Fundamental design features and a mathematical treatment under ideal conditions are set forth for eventually showing how to unroll an informative (though expensive) program of viscometry on the base of harmonic Fourier analysis. In an appendix, the ascertainment of material coefficients is exemplified on specific constitutive assumptions so as to suggest analogously handling other instances on demand.