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Spectral flatness factor and ‘intermittency’ in turbulence and in non-linear noise

Published online by Cambridge University Press:  28 March 2006

D. A. Kennedy  and
S. Corrsin
D. A. Kennedy
Affiliation:
Mechanics Department, The Johns Hopkins University
S. Corrsin
Affiliation:
Mechanics Department, The Johns Hopkins University
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Abstract

The flatness factor F of the signal transmitted through a band-pass filter has been measured for the turbulence in a free shear layer and for a squared Gaussian noise. They both show flatness factor increasing with centre frequency fc. In the turbulence, band-passed signals look intermittent and have larger F than the full signal, but in the squared noise, band-passed signals all have smaller F than the full signal although they look more intermittent.

It is shown analytically that the derivative of a smoothed, squared Gaussian noise may have flatness factor either greater or less than the undifferentiated signal.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 10 , Issue 3 , May 1961 , pp. 366 - 370
Copyright
© 1961 Cambridge University Press

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References

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