Similarity-Law Entrainment Method for Two-Dimensional Turbulent Boundary Layers in Pressure Gradients.
Abstract
Analytical relations have been derived for calculating a developing two-dimensional turbulent boundary layer in a pressure gradient from two simultaneous differential equations: momentum and shape parameter. An entrainment method is used to obtained the shape parameter equation. Both equations incorporate the velocity similarity laws that provide a two-parameter velocity profile general enough to include any range of Reynolds numbers. The entrainment factor is based on the characteristics of equilibrium pressure gradients in a way which can accommodate the usual pressure gradients found in engineering applications. The method includes a newly formed wake modification for the similarity laws as well as added effects due to low Reynolds numbers. The variation of momentum loss boundary-layer thickness, local skin friction, and local velocity profile may be calculated for the boundary layers on hydrofoils and two-dimensional appendages. The various formulations are shown to correlate well with available experimental data. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1975
- Accession Number
- ADA031733
Entities
People
- Paul S. Granville