This model describes the simplest type of flow behavior, namely that the material’s viscosity is constant, independent of the applied shear rate. The model is expressed in terms of the shear stress/shear rate as follows:
Examples of simple fluids to fit the Newtonian model are water, sugar solutions, glycerol, oils, etc.
More complex fluids are either the power law (viscosity a function of rate) or the Bingham fluid (Newtonian fluid with a yield).
