Prediction of unsteady turbulent boundary layers with flow reversal
Abstract
The prediction of unsteady turbulent boundary layers with flow reversal is of importance in a number of aerodynamic problems, notably in dynamic stall, buffeting and gust studies. However, some of the more popular turbulence models implicitly assume that the wall shear is positive and their extension to unsteady flows with flow reversal is not easy. It requires a modification of the functional form of the law of the wall and the manner in which the wall shear is determined. Two near-wall assumptions are considered here. In the first, the near wall grid point is located in the logarithmic region and the law of the wall is used to link the flow properties at this grid point to the wall. In the second, a Van Driest formulation due to Cebeci and Smith is used and implies that the grid point closest to the wall will occur in the viscous sublayer.
- Publication:
-
Presented at the 2d Symp. on Turbulent Shear Flows
- Pub Date:
- 1979
- Bibcode:
- 1979tsf..symp....2C
- Keywords:
-
- Reversed Flow;
- Turbulent Boundary Layer;
- Unsteady Flow;
- Mathematical Models;
- Partial Differential Equations;
- Turbulence Models;
- Fluid Mechanics and Heat Transfer