Reattachment Studies of an Oscillating Airfoil Dynamic Stall Flow Field

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Chandrasekhara_reattachment_1991_paper.pdf (925.13 KB)
Authors
Ahmed, S.
Chandrasekhara, M.S.
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Advisors
Date of Issue
1991-09
Date
September 23-25, 1991
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Abstract
The reattaching flow over an oscillating airfoil executing large amplitude sinusoidal motion around a mean angle of attack of 10 degrees has been studied using the techniques of stroboscopic schlieren, two component laser Doppler velocimetry and point diffraction interferometry, for a free stream Mach number of 0.3 and a reduced frequency of 0.05. The results show that the dynamically stalled flow reattaches in a process that begins when the airfoil is very close to the static stall angle on its downward stroke and progresses over the airfoil through a large range of angles of attack as the airfoil angle decreases to about 6 degrees. The airfoil suction peak shows a dramatic rise as the static stall angle is approached and the velocity profiles develop such that the flow near the surface is accelerated. The process completes through the disappearance of a separation bubble that forms over the airfoil.
Type
Conference Paper
Description
URI
https://hdl.handle.net/10945/50449
Series/Report No
Department
Organization
Naval Postgraduate School (U.S.)
Identifiers
NPS Report Number
Sponsors
Army Research Office grant (MIPR-ARO-132-90) to the Naval Postgraduate School
AFOSR (MIPR-91-0007)
NAVAIR
Funder
Army Research Office grant (MIPR-ARO-132-90) to the Naval Postgraduate School
AFOSR (MIPR-91-0007)
NAVAIR
Format
18 p.
Citation
AIAA 9th Applied Aerodynamics Conference, September 23-25, 1991 / Baltimore, MD
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This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.
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