Wall effects in simple shear of dilute polymer solution: Exact results for very narrow and very wide channels

The effect of the presence of walls for simple shear of a dilute macromolecular solution is studied. For Gaussian dumbbell model macromolecules, exact analytic results for all rheological quantities are obtained for very small and very large (but finite) channels, respectively. The concept of a slip velocity and of a pure solvent layer close to either wall, though useful for the shear stresses, cannot be used for the normal stresses.