EVALUATION OF MATERIAL FUNCTIONS FOR STEADY ELONGATIONAL FLOWS.

Abstract

A general method is suggested for classifying steady, isochoric elongational flows. A procedure is outlined to determine from experimental data the material functions which, as shown by Coleman and Noll, characterize incompressible simple fluids in steady elongational flows. For uniaxial and biaxial elongation, two possible definitions of these material functions are obtained. As an illustration, predictions for material functions are given for Lodge's rubberlike liquid constitutive equation.