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Closed-Loop Control of Vortex Formation in Separated FlowsIn order to phase lock the flow at the desired shedding cycle, particularly at Phi,best, We designed a feedback compensator. (Even though the open-loop forcing at Wf below Wn can lead to phase-locked limit cycles with a high average lift,) This feedback controller resulted in the phase-locked limit cycles that the open-loop control could not achieve for alpha=30 and 40 Particularly for alpha=40, the feedback was able to stabilize the limit cycle that was not stable with any of the open-loop periodic forcing. This results in stable phase-locked limit cycles for a larger range of forcing frequencies than the open-loop control. Also, it was shown that the feedback achieved the high-lift unsteady flow states that open-loop control could not sustain even after the states have been achieved for a long period of time.
Document ID
Document Type
Conference Paper
Colonius, Tim
(California Inst. of Tech. Pasadena, CA, United States)
Joe, Won Tae
(California Inst. of Tech. Pasadena, CA, United States)
MacMynowski, Doug
(California Inst. of Tech. Pasadena, CA, United States)
Rowley, Clancy
(Princeton Univ. Princeton, NJ, United States)
Taira, Sam
(Princeton Univ. Princeton, NJ, United States)
Ahuja, Sunil
(Princeton Univ. Princeton, NJ, United States)
Date Acquired
August 24, 2013
Publication Date
February 1, 2010
Publication Information
Publication: Minnowbrook VI: 2009 Workshop on Flow Physics and Control for Internal and External Aerodynamics
Subject Category
Distribution Limits
Public Use Permitted.
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