| Abstract: | Viscosity data of an aluminum soap solution, a polyisobutylene solution, a polyacrylamide solution, and ten polystyrene solutions have been analysed using two rheological models: the Carreau model A and the Ellis model. The model parameters were obtained by non-linear regression. The importance of the zero-shear viscosity for design purposes is illustrated by observing the appearance of a master curve in the representation of the dimensionless viscosity versus the product of the zero-shear viscosity by the shear rate. A linear relation is shown to exist between the logarithm of the zero-shear viscosity and the polymer concentration. It is asserted that either model should replace advantageously the commonly used power-law expression. |
