|We consider viscous, Newtonian, incompressible fluid inside a
cylinder or cylindrical shell. We discuss the convergence of
the Navier-Stokes equations to the corresponding solutions of the
equations as viscosity vanishes for the case of planar, circularly
symmetric flows, and the behavior in the boundary layer. Symmetry
the problem linear and 2D, but we allow for rough angular velocities.
also discuss the case of plane parallel channel flow, where the