Comparison of large-scale amplitude modulation in turbulent boundary layers, pipes, and channel flows

Recent Investigations by Monty et al. [J. Fluid Mech 632, 431 (2009)] showed that important modal differences exist between channels/pipes and boundary layers, mainly in the largest energetic scales In addition. Mathis et al. [J. Fluid Mech. 628, 311 (2009)] recently reported and quantified a nonlinear scale Interaction in zero-pressure gradient turbulent boundary layers, whereby the larp-e-scale motion amplitude modulates the small-scale motions. In this study, a comparison of this modulation effect of the streamwise velocity component IS undertaken for all three flows for matched Reynolds number and measurement conditions. Despite the different large-scale phenomena in these internal and external wall-bounded flows, the results show that their amplitude modulation Influence remains invariant in the inner region with some differences appearing in file outer region. (C) 2009 American Institute of Physics. [doi: 10.1063/1.3267726] C