An Integral Prediction Method for Three-Dimensional Turbulent Boundary Layers on Rotating Blades.
Abstract
A general formulation of the boundary-layer computation scheme on the surface of a rotating blade is presented. Momentum-integral methods, together with the three-dimensional entrainment equation for a rotating disk, are used to calculate the three-dimensional turbulent boundary layer in an orthogonal streamline coordinate system. First-order finite-difference methods are used to solve the resulting boundary-layer equations. The unknown variables are the streamwise momentum thickness, the shape parameter, and the streamline slope at the surface. The boundary-layer calculation method is combined with existing geometrical and inviscid potential-flow computer codes for rotating blades to form an efficient turbulent boundary-layer computer code. For a given potential-flow solution, a typical boundary-layer computation requires less than 10 seconds computer time on the Burroughs 7700 high-speed computer. Boundary-layer predictions are presented for several rotating blades. Computed results are shown to be in agreement with experimental data for a simple rotating body. For the examples considered, displacement of the mid-chord point of a blade from a straight radial line is predicted to reduce the computed values of local skin friction coefficient, with an estimated increase in overall efficiency of about one percentage point. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1981
- Accession Number
- ADA100620
Entities
People
- Nancy C. Groves