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Dynamical eigenfunction decomposition of turbulent channel flowThe results of an analysis of low-Reynolds-number turbulent channel flow based on the Karhunen-Loeve (K-L) expansion are presented. The turbulent flow field is generated by a direct numerical simulation of the Navier-Stokes equations at a Reynolds number Re(tau) = 80 (based on the wall shear velocity and channel half-width). The K-L procedure is then applied to determine the eigenvalues and eigenfunctions for this flow. The random coefficients of the K-L expansion are subsequently found by projecting the numerical flow field onto these eigenfunctions. The resulting expansion captures 90 percent of the turbulent energy with significantly fewer modes than the original trigonometric expansion. The eigenfunctions, which appear either as rolls or shearing motions, possess viscous boundary layers at the walls and are much richer in harmonics than the original basis functions.
Document ID
19910050352
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Ball, K. S. (Texas, University Austin, United States)
Sirovich, L. (Brown University Providence, RI, United States)
Keefe, L. R. (NASA Ames Research Center Moffett Field, CA, United States)
Date Acquired
August 15, 2013
Publication Date
April 5, 1991
Publication Information
Publication: International Journal for Numerical Methods in Fluids
Volume: 12
ISSN: 0271-2091
Subject Category
FLUID MECHANICS AND HEAT TRANSFER
Funding Number(s)
CONTRACT_GRANT: N00014-86-K-0754
Distribution Limits
Public
Copyright
Other