Abstract:
A calculation method has been developed which uses the compressible forms of the boundary-layer momentum integral and entrainment equations in a general, curvilinear surface coordinate system in which the axes are not necessarily orthogonal. Both the Mager and Johnston representations of the crossflow velocity profile can be used. The set of equations used is hyperbolic and is solved numerically by a simple explicit finite difference method. In cases where the metric coefficients of the coordinate system used are not known analytically a method is given for obtaining them from the Cartesian coordinates of the surface. A method is also presented for determining the external velocity field from a given pressure distribution. Comparisons are given of predictions of the boundary-layer method with the experimental results of Johnston, Vermeulen, East, van den Berg and Elsenaar, and Hall and Dickens. These results, involving five different coordinate systems, were all obtained using the same computer program.