A four-constant model for viscoelastic fluids

✍ Scribed by T.W. Spriggs

• Publisher: Elsevier Science
• Year: 1965
• Tongue: English
• Weight: 763 KB
• Volume: 20
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(65)80091-4

✦ Synopsis

A nonlinear extension of the generalized Maxwell model is proposed as a constitutive equation for viscoelastic fluids. Expressions for complex-viscosity, oscillatory normal stresses, non-Newtonian viscosity and two normal stress differences are given in terms of four parameters. Comparison is made with M. C. Williams' complex-viscosity data for 1.46 % polyethylene oxide in water and with Williams normal stress and non-Newtonian viscosity data for 1.54% hydroxyethylcellulose in water.

The viscosity function from the proposed model agrees with the Ellis model in the regions of high and low shear rate. The expressions for the oscillatory shear stresses and normal stresses agree with those derived from a special case of Coleman and Nell's theory of second order viscoelasticity.