Unsteady momentum integral analysis of the laminar boundary layer on an elliptic cylinder oscillating in pitch
Abstract
A theoretical study was conducted to examine the laminar, two-dimensional, unsteady boundary layer on a slender elliptic cylinder oscillating periodically in a steady uniform freestream. For comparison, the solution was also obtained for the case in which the elliptic cylinder is stationary in a freestream of periodically varying incidence. The essential features of the analysis were the representation of the boundary layer parameters as a steady term plus an unsteady perturbation proportional to the incremental angle-of-attack change, the transformation of the usual boundary layer coordinate system such that the location of the separation point appears steady in the new coordinate system, and a relation between the rate at which vorticity is shed into the wake and the time rate of change of circulation. The transformed boundary layer equations were solved by a modification of an unsteady momentum integral technique.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- June 1974
- Bibcode:
- 1974PhDT........21J
- Keywords:
-
- Elliptical Cylinders;
- Laminar Boundary Layer;
- Pitch (Inclination);
- Aerodynamic Stalling;
- Angle Of Attack;
- Boundary Layer Separation;
- Free Flow;
- Hysteresis;
- Fluid Mechanics and Heat Transfer