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Low Reynolds Number Wing Response to an Oscillating Freestream With and Without Feed Forward Control

Williams, David and Quach, Vien and Kerstens, Wesley and Buntain, Seth and Tadmor, Gilead and Rowley, Clarence and Colonius, Tim (2009) Low Reynolds Number Wing Response to an Oscillating Freestream With and Without Feed Forward Control. In: 47th AIAA Aerospace Sciences Meeting including The New Horizons Forum and Aerospace Exposition, 5-8 January 2009, Orlando, FL.

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The unsteady lift of a low Reynolds number wing in an oscillating freestream is documented in terms of its amplitude and phase. The phase variation of the lift relative to the freestream velocity shows a larger phase difference than predicted by classical unsteady flow theory. A constant time delay between the lift and the actuator was observed to be τ^+ = t_(delay)U/c = 5.3 when normalized by the freestream speed and chord. Feed forward control of pulsed-jet actuators is used to modulate the lift coefficient of the wing, in an attempt to suppress the lift oscillations. Suppression of the fluctuating lift at the fundamental frequency was partially successful, but additional "noise" was added to harmonics of the lift signal by the controller.

Item Type:Conference or Workshop Item (Paper)
Related URLs:
URLURL TypeDescription Paper Paper
Rowley, Clarence0000-0002-9099-5739
Colonius, Tim0000-0003-0326-3909
Additional Information:© 2009 by David R. Williams. Published by the American Institute of Aeronautics and Astronautics, Inc., with permission. Published Online: 15 Jun 2012. The support for this work by the U.S. Air Force Office of Scientific Research MURI (FA9550-05-0369) with program manager Dr. Fariba Fahroo is gratefully appreciated. We also acknowledge the support from the Illinois NASA Space Grant Consortium for Wes Kerstens.
Funding AgencyGrant Number
Air Force Office of Scientific Research (AFOSR)FA9550-05-0369
Subject Keywords:Aerospace Systems, Operations and Life Cycle
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Other Numbering System NameOther Numbering System ID
AIAA Paper2009-143
Record Number:CaltechAUTHORS:20190717-102319638
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:97207
Deposited By: Melissa Ray
Deposited On:18 Jul 2019 16:33
Last Modified:16 Nov 2021 17:29

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