Laser-Doppler velocimetry and viscous computation of the flow through a compressor cascade near stall
By: Andrew J. H. Williams
Publisher: Naval Postgraduate School; Available from National Technical Information Service
Published: 1995
Place of publication: Monterey, Calif; Springfield, Va
Language: eng
Number of pages: 103
Description: Laser-Doppler velocimeter measurements were made in the flow field of a stalled cascade of controlled-diffusion stator blades. Tests were conducted at 10 degrees of incidence above the design inlet-flow angle in order to verify previous measurements. A unique method of data presentation was offered to characterize the unsteady positive and negative velocities about their mean. Laser-sheet flow visualization was performed and showed the unsteadiness of the stalling phenomena within the blade row passages. Additionally, a leading-edge separation bubble was observed and reversed flow was measured within the bubble using the laser-Doppler anemometer. Power-spectral density and auto-correlation analysis results are presented. In parallel with the experimental measurements, a computational fluid-dynamics study was initiated in an attempt ultimately to predict stall. Viscous flow computations were completed at on-design and near-stall conditions. Pressure distributions, separation bubble re-attachment locations, and loss predictions were compared to previous experimental studies. Generally good agreement was obtained for on-design conditions with degradation in prediction nearing stall.
Notes: Thesis advisor(s): Garth V. Hobson.

"June 1995."

Thesis (M.S. in Aeronautical Engineering) Naval Postgraduate School, June 1995.

Includes bibliographical references.

Approved for public release; distribution unlimited.

Also available online.

Mode of access: World Wide Web.

System requirements: Adobe Acrobat Reader.

US Naval Reserve (USNR) author.

dk/dk cc:9996