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, twodimensional, 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 angleofattack 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