The laminar boundary layer produced by the rotating flow of a viscous incompressible fluid over a finite stationary disk is considered. The boundary-layer equations for flows in which the external tangential velocity ' varies as some power of the radius and the external radial velocity is zero are solved using several variations of the Karmah-Pohlhausen momentum-integral method. The results of numerical integration of the boundary-layer equations are compared to the momentum-integral solutions of Taylor and Cooke and the series solution of Mack. A numerical error in Cooke's original solution ie corrected and a new solution presented, the results do not change substantially.nIf the outer flow is a potential vortex (n = -1), the methods investigated yield widely varying results for radial inflow and the axial velocity distribution in the boundary layer, the simplest integral method employed agrees best with the series solution. For n = -0. 75 and 0. 5, all methods (except Cooke) yield results in close agreement with each other.nThe restrictions imposed by the various methods are discussed. It is noted that the tangential momentum equation controls the nature of the radial inflow. For n - -1,the introduction of a third scaling parameter may lead to erroneous results.
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