Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published January 1987 | Published
Journal Article Open

Response of the Cavity Shear Layer Oscillations to External Forcing

Gharib, M. ORCID icon

Abstract

Influence of externally forced initial flow conditions on axisymmetric cavity shear layer was studied. A sinusoidally heated strip upstream of the cavity excited Tollmien-Schlichting waves that, after amplification by the boundary layer, were introduced to the cavity shear layer. It is shown that by selecting a forcing frequency, which satisfies a phase difference criterion between two comers of the cavity and has an amplitude that is above the threshold amplitude, it is possible to excite a naturally nonoscillating shear layer. It is also shown that the frequency and amplitude of the oscillation in the self sustained mode can be controlled through external forcing. By using a feed-back control scheme, up to 40% reduction of the velocity fluctuation level can be obtained.

Additional Information

© 1986 American Institute of Aeronautics and Astronautics, Inc. Presented as Paper 85-0528 at the AIAA Shear Flow Control Conference, Boulder, CO, March 12-14, 1985; received Sept. 17, 1985; revision received Feb. 24, 1986. This paper is based on work from the Ph.D. Thesis by the author, which was carried out at the Jet Propulsion Laboratory, California Institute of Technology. The work was sponsored by U. S. Army Research Office Contract 7134E. The author is grateful for assistance in various forms from A. Roshko, H. W. Liepmann, D. M. Nosenchuck, and V. Sarohia.

Attached Files

Published - Gharib_1987p43.pdf

Files

Gharib_1987p43.pdf
Files (682.6 kB)
Name Size Download all
md5:b67ca1902e3f93fe4c174b6d655b9ebf
682.6 kB Preview Download

Additional details

Created:
August 19, 2023
Modified:
March 5, 2024