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Acceleration Statistics as Measures of Statistical Persistence of Streamlines in Isotropic Turbulence

S. Goto·D. R. Osborne·J. C. Vassilicos·J. D. Haigh
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Abstract

We introduce the velocity (Vs) of stagnation points as a means to characterise and measure statistical persistence of streamlines. Using theoretical arguments, Direct Numerical Simulations (DNS) and Kinematic Simulations (KS) of three-dimensional isotropic turbulence for different ratios of inner to outer length scales L/eta of the self-similar range, we show that a frame exists where the average =0, that the r.m.s. values of acceleration (a'), turbulent fluid velocity (u') and Vs are related by La'/(u'^2) ~ (Vs/u')(L/eta)^(2/3+q) and that Vs/u' ~ (L/eta)^q with q=-1/3 in Kolmogorov turbulence, q=-1/6 in current DNS and q=0 in our KS. The statistical persistence hypothesis is closely related to the Tennekes sweeping hypothesis.

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S. Goto, D. R. Osborne, J. C. Vassilicos, J. D. Haigh. 2004-11-19. Acceleration Statistics as Measures of Statistical Persistence of Streamlines in Isotropic Turbulence. https://doi.org/10.1103/physreve.71.015301

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