Measurement of the Normal Stress Coefficients By Means of an Optical Technique
The double exposure speckle photograph is applied to the Weissenberg effect in order to determine the two normal stress coefficients. Two different geometries are employed: coaxial cylinders and half-filled concentric spheres. These first results prove the feasibility of the method and display the limits of the theory which is used to fit the experimental data.
KeywordsFree Surface Normal Stress Difference Photographic Plate Coaxial Cylinder Concentric Sphere
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