Accession Number:

ADA247517

Title:

Control of Two- and Three-Dimensional Wake Instabilities from Bluff-Bodies

Descriptive Note:

End-of-the-fiscal-year-letter,

Corporate Author:

LEHIGH UNIV BETHLEHEM PA

Personal Author(s):

• Rockwell, Donald
• Ramberg, Steve
• Rood, Edwin

Report Date:

1991-09-30

Pagination or Media Count:

14.0

Abstract:

This program addresses the manipulation of flow structure and spectral content of near and far wake instabilities from bluff bodies by 1 generation of varying phase shift and wavelength of vortex shedding relative to body motion by sinusoidal, amplitude-modulated, and frequency modulated excitation 2 alteration of mean boundary conditions at separation via boundary layer control and 3 modification of three dimensional spanwise geometry of the body surface. In parallel with these technical objectives, new types of experimental techniques will be developed. Emphasis will be on laser diagnostics, and interactive image display and analysis exploiting new types of graphic supercomputers. Particular effort will be devoted to the development of a high resolution particle image velocimetry PIV system that allows acquisition of velocity information over entire planes of the flow. Two- and three-dimensional interpretations of the flow structure in color and real time are attainable using graphics supercomputers.

Descriptors:

• *VELOCITY
• ACQUISITION
• REAL TIME
• EXCITATION
• FREQUENCY MODULATION
• MOTION
• TEST METHODS
• VORTEX SHEDDING
• DISPLAY SYSTEMS
• SURFACES
• BOUNDARIES
• SPECTRA
• LASER APPLICATIONS
• WAKE
• GRAPHICS
• DIAGNOSIS(GENERAL)
• FLOW
• INTERACTIVE GRAPHICS
• SUPERCOMPUTERS
• MEAN
• INSTABILITY
• BOUNDARY LAYER CONTROL
• PHASE SHIFT
• THREE DIMENSIONAL FLOW
• IMAGE PROCESSING

Subject Categories:

• Computer Hardware

Distribution Statement:

APPROVED FOR PUBLIC RELEASE