Plenary Speech:

Empirical Constitutive Equations - From Monotonous to Non-Monotonous Flow Curves

Professor Petr Filip
Institute of Hydrodynamics
Academy of Sciences of the Czech Republic
Pod Patankou 5, 166 12 Prague 6
Czech Republic

Abstract: A number of parameters appearing in the 'classical' empirical constitutive equations (rheological equations of state) describing viscosity behaviour of non-Newtonian fluids usually oscillate between two (power-law or Bingham model) and five (as e.g. Carreau-Yasuda model). With the onset of new rheologically more complex materials exhibiting non-monotonous behaviour of flow curves this range (2-5) is no longer tenable and more additional parameters are required for a proper description of the flow curves. The present contribution summarises basic classical monotonous models, and analyses a non-monotonous problem for the cases: shear viscosity vs. shear rate and shear viscosity vs. shear stress.

Brief Biography of the Speaker:
Study:
Charles University, Faculty of Mathematics and Physics, specialty applied mathematics, Prague
Ph.D. Study:
Institute of Mathematics, Czechoslovak Academy of Sciences, Prague
Dept of Partial Differential Equations
Ph.D.degree, Thesis: 'Oscillation of Wave Equation in Two Dimensions'

now with The Institute of Hydrodynamics, Academy of Sciences of the Czech Republic in Prague
Fields of interest: Rheology, Fluid Mechanics
Professional membership: The Society of Rheology, The Polymer Processing Society