Accession Number:

ADA232692

Title:

Vortex System Evolution in 2- and 3-D Swept Trailing Edge Flows

Descriptive Note:

Final rept. 1 Sep 1987-31 Aug 1989

Corporate Author:

MCDONNELL DOUGLAS RESEARCH LABS ST LOUIS MO

Report Date:

1990-07-24

Pagination or Media Count:

31.0

Abstract:

Instability wavefront orientation and vortex system interaction were studied in a swept-trailing-edge mixing layer and in a slanted nozzle jet flowfield at low subsonic velocities. Flow visualization and image processing, and hot-wire data comprised the main body of experimental observations. The response of full-span wave systems of swept and unswept orientation were documented as a function of acoustic excitation introduced through a thin slot at the trailing edge. The lateral spreading of a wave system with only partial- span excitation was shown to be asymmetrical in a swept mixing layer. The jet flowfield was studied using a simultaneous axial and transverse laser sheet illumination. Excitation frequency-and amplitude-dependence of instability wave system orientation was characterized. Digitized flow visualization images were decomposed to show the axial and helical shear layer modes.

Subject Categories:

  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE