Published in AIAA 25th Aerospace Sciences Meeting: Reno, Nevada, January 12, 1987. AIAA 87-0167. Published with permission of the American Institute of Aeronautics and Astronautics, Inc. Publisher website: http://www.aiaa.org/content.cfm?pageid=2.
NOTE: At the time of publication, the author William Durgin was not yet affiliated with Cal Poly.
Flow past deep wall cavities exhibits strong interaction with the standing wave system in the cavity. The shear layer separating the exterior flow from the cavity flow supports instabilities which excite the normal cavity modes. In turn, the cavity wave system reinforces the instabilities. Experimental studies have shown that two distinct instability modes are encountered as the external velocity is increased. The pressure coefficient versus Strouha1 number behavior reveals two maxima which correspond to different instability modes of the shear layer. Flow visualization studies have shown that these modes correspond to distinct shear 1ayer vortex structures. At high velocities, single large-scale vortices are formed on the interface. At lower velocities, two vortices are present, simultaneously.