Читать книгу The Rheology Handbook - Thomas Mezger - Страница 119

or as

simplified:

Viscosity curve model function with Carreau constant c1 [s], Carreau exponent p, slope value c of the viscosity curve at high shear rates on a log/log scale, and the shear rate value γ ̇ c at the bend between the plateau of η0 and the falling η-curve in the range of shear-thinning behavior (of 1968/1972 [3.44]).

For the simplified version “Carreau 0”, the same assumptions are made as for the “Cross 0” model above. The Cross and Carreau model functions are similar and they are often used by people working in R & D in the polymer industry. Modifications of the Carreau model:

1) Carreau/Gahleitner :

Viscosity curve model function with Gahleitner exponent p1. For p1 = 2, the model is identical to the Carreau model (in 1989 [3.45]).

2) Carreau/Yasuda :

Viscosity curve model function with Yasuda exponent p1, relaxation time λ [s], and power-law-

index p. It counts: p = 1 for ideal-viscous flow behavior,

p < 1 for shear-thinning, p > 1 for shear-thickening (of 1981 [3.46] [3.47]).