On the intermittency exponent of the turbulent energy cascade

Jochen Cleve; Martin Greiner; Bruce R. Pearson; Katepalli R. Sreenivasan

doi:10.1103/physreve.69.066316

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On the intermittency exponent of the turbulent energy cascade

Jochen Cleve·Martin Greiner·Bruce R. Pearson·Katepalli R. Sreenivasan

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Abstract

We consider the turbulent energy dissipation from one-dimensional records in experiments using air and gaseous helium at cryogenic temperatures, and obtain the intermittency exponent via the two-point correlation function of the energy dissipation. The air data are obtained in a number of flows in a wind tunnel and the atmospheric boundary layer at a height of about 35 m above the ground. The helium data correspond to the centerline of a jet exhausting into a container. The air data on the intermittency exponent are consistent with each other and with a trend that increases with the Taylor microscale Reynolds number, R_λ, of up to about 1000 and saturates thereafter. On the other hand, the helium data cluster around a constant value at nearly all R_λ, this being about half of the asymptotic value for the air data. Some possible explanation is offered for this anomaly.

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Jochen Cleve, Martin Greiner, Bruce R. Pearson, Katepalli R. Sreenivasan. 2004-02-04. On the intermittency exponent of the turbulent energy cascade. https://doi.org/10.1103/physreve.69.066316

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