Measurement of the Weissenberg effect by holographic interferometry

Abstract

A method of determining the second order viscometric function of a simple fluid is described. It is based on theoretical work by G. Böhme which suggests that these constants can be estimated by measurement of the Weissenberg Effect. Comparison of the Weissenberg Effect in spherical and cylindrical symmetry yields the constants. A technique for making holograms of steady dynamic fluids is developed and double exposure interferometric holography is used to determine the surface shapes. Measurements of the two constants are made for a mildly non-Newtonian fluid. Though only orders of magnitude are obtained, they agree in sign and ratio to measurements made by other techniques. Show more