HR: 17:05h
AN: NG54A-04 INVITED     [Abstracts]
TI: Universality of scaling laws in correlation between velocity and shear stress in turbulent boundary layers
AU: * V., V
EM: venu@caos.iisc.ernet.in
AF: Centre for Atmospheric and Oceanic Sciences, Indian Institute of Science, Bangalore, KA 560012, India
AU: Porte-Agel, F
EM: fporte@umn.edu
AF: St. Anthony Falls Laboratory, University of Minnesota 2 3rd Avenue SE, Minnneapolis, MN 55414, United States
AU: Heuer, W
EM: heuer@aem.umn.edu
AF: Aerospace and Engineering Mechanics, University of Minnesota Akerman Hall 110 Union Street SE, Minneapolis, MN 55455, United States
AU: Marusic, I
EM: marusic@aem.umn.edu
AF: Aerospace and Engineering Mechanics, University of Minnesota Akerman Hall 110 Union Street SE, Minneapolis, MN 55455, United States
AB: In this study, we analyse simultaneous measurements (at 50 Hz) of velocity at several heights and shear stress at the surface made during the Utah field campaign for the presence of ranges of scales, where distinct scale-to-scale interactions between velocity and shear stress can be identified. We find that our results are similar to those obtained in a previous study [Venugopal et al., 2003] (contrary to the claim in V2003, that the scaling relations might be dependent on Reynolds number) where wind tunnel measurements of velocity and shear stress were analysed. We use a wavelet-based scale-to-scale cross-correlation to detect three ranges of scales of interaction between velocity and shear stress, namely, (a) inertial subrange, where the correlation is negligible; (b) energy production range, where the correlation follows a logarithmic law; and (c) for scales larger than the boundary layer height, the correlation reaches a plateau.
DE: 3235 Persistence, memory, correlations, clustering (3265, 7857)
DE: 3280 Wavelet transform (3255, 4455)
DE: 3307 Boundary layer processes
DE: 4475 Scaling: spatial and temporal (1872, 3270, 4277)
DE: 4490 Turbulence (3379, 4568, 7863)
SC: Nonlinear Geophysics [NG]
MN: 2007 Joint Assembly