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Global Instability on Laminar Separation Bubbles-RevisitedIn the last 3 years, global linear instability of LSB has been revisited, using state-of-the-art hardware and algorithms. Eigenspectra of LSB flows have been understood and classified in branches of known and newly-discovered eigenmodes. Major achievements: World-largest numerical solutions of global eigenvalue problems are routinely performed. Key aerodynamic phenomena have been explained via critical point theory, applied to our global mode results. Theoretical foundation for control of LSB flows has been laid. Global mode of LSB at the origin of observable phenomena. U-separation on semi-infinite plate. Stall cells on (stalled) airfoil. Receptivity/Sensitivity/AFC feasible (practical?) via: Adjoint EVP solution. Direct/adjoint coupling (the Crete connection). Minor effect of compressibility on global instability in the subsonic compressible regime. Global instability analysis of LSB in realistic supersonic flows apparently quite some way down the horizon.
Document ID
20100018576
Acquisition Source
Glenn Research Center
Document Type
Conference Paper
Authors
Theofilis, Vassilis
(Universidad Politecnica de Madrid Madrid, Spain)
Rodriquez, Daniel
(Universidad Politecnica de Madrid Madrid, Spain)
Smith, Douglas
(Universidad Politecnica de Madrid Madrid, Spain)
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
Aerodynamics
Funding Number(s)
CONTRACT_GRANT: FA8655-06-1-3066
Distribution Limits
Public
Copyright
Public Use Permitted.
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