(2) Influence of
coefficient of viscosity on the floor
At higher shear rates there is no significant variation and the
coefficient of viscosity is almost constant over the entire range of shear rate.
As a first approximation, the following expression (Barus equation) can be used to determine the parameter, [[beta].sub.p], known as the pressure
coefficient of viscosity:
In the exponential relations (15, 16) [beta] is the pressure
coefficient of viscosity, P stands for the gauge pressure, [alpha] means the temperature
coefficient of viscosity, and T and [T.sub.r] are tested and reference temperatures, respectively.
It was noted that the concentration
coefficient of viscosity, [Psi], was a considerably negative value, as expected.