Calculation Methods for Three-dimensional Turbulent Boundary Layers

Abstract

Five methods for the approximate solution of the momentum integral equations for the three dimensional turbulent boundary layer are presented. These include the removal of the usual small cross-flow velocity restriction and the development of the streamwise shape parameter is calculated by means of an extension of Head's entrainment hypothesis. The predictions of these theories and of those of a method due to Cooke are then compared with the results of a series of experiments with an apparatus designed to simulate the case of an infinite yawed wing. A considerable discrepancy is shown to exist between theory and experiment which is attributed either to the streamwise skin friction being inadequately represented by an expression derived from two-dimensional flow or possibly, if less likely, to the neglect of certain terms in the derivation of the streamwise momentum-integral equation.