Wavelet analysis of wall turbulence to study large-scale modulation of small scales

WJ Baars; KM Talluru; N Hutchins; I Marusic

Journal article

Wavelet analysis of wall turbulence to study large-scale modulation of small scales

WJ Baars, KM Talluru, N Hutchins, I Marusic

Experiments in Fluids | Published : 2015

DOI: 10.1007/s00348-015-2058-8

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Abstract

Wavelet analysis is employed to examine amplitude and frequency modulations in broadband signals. Of particular interest are the streamwise velocity fluctuations encountered in wall-bounded turbulent flows. Recent studies have shown that an important feature of the near-wall dynamics is the modulation of small scales by large-scale motions. Small- and large-scale components of the velocity time series are constructed by employing a spectral separation scale. Wavelet analysis of the small-scale component decomposes the energy in joint time–frequency space. The concept is to construct a low-dimensional representation of the small-scale time-varying spectrum via two new time series: the instant..

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University of Melbourne Researchers

Nicholas Hutchins Author

Ivan Marusic Author

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Grants

Awarded by Australian Research Council

Funding Acknowledgements

The authors wish to gratefully acknowledge the Australian Research Council for financial support. Furthermore, we would like to give special thanks to Dr. Daniel Chung for insightful discussions.