Three-Dimensional Boundary-Layer Computation on the Stationary End-Walls of Centrifugal Turbomachinery

Abstract

An integral entrainment computation technique is presented for the three-dimensional boundary-layer growth on the stationary end-walls of centrifugal turbomachinery. The analytical model assumes axisymmetric inviscid core flow and viscous flow in the wall region, and the interaction between the two layers is considered. A novel form of the three-dimensional boundary-layer equations is presented. The form is physically appealing for this axisymmetric application and provides distinct advantages in the prediction of boundary-layer growth. It is demonstrated that it is essential to use the meridional boundary-layer profile to compute the Head entrainment function for this type of flow, as opposed to the streamwise velocity profile, as is more commonly done. Comparison with experimental measurements shows good agreement in the integral parameters. In addition, good agreement with experimental velocity profiles was achieved for a separating and reattaching flow.