Laser-Doppler Velocimeter Measurements in a Cascade of Controlled Diffusion Compressor Blades at Stall
Abstract
An incipient compressor blade stall has been generated and examined in the Low Speed Cascade Wind Tunnel at the Turbopropulsion Laboratory. The test blades were a controlled-diffusion design with solidity 1.67, and stalling occurred at 10 degrees of incidence above the design inlet air angle. Tufting and laser-sheet flow-visualization techniques showed that the stalling process was unsteady, and occurred over the whole cascade of 20 blades. Detailed laser- doppler velocimeter measurements over the suction side of the blades showed regions of continuous and intermittent reversed flow. The measurements of the continuous reversed flow region at the leading edge were the first data to be obtained of flow within the leading edge separation bubble. The intermittent reversed flow region measurements quantified what was observed in the flow visualization studies. Blade surface pressure measurements showed a decrease in normal force on the blade as would be expected at stall.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1994
- Accession Number
- ADA283416
Entities
People
- Humberto J. Rickel
Organizations
- Naval Postgraduate School