Lagrangian Intermittency Based on an Ensemble of Gaussian Velocity Time Series
We show that Lagrangian intermittency in fully developed turbulence can be captured in terms of an ensemble of Gaussian velocity time series. This is achieved by letting the individual ensemble members vary with respect to their correlation function. We briefly discuss how this can be analytically captured in terms of a suitably defined characteristic functional. Moreover, we present a numerical implementation of the ensemble showing a continuous change from Gaussian to non-Gaussian increment distributions for a decreasing time lag. In an outlook we show first results on the application to data from direct numerical simulation.
This work was supported by the Max Planck Society. We gratefully acknowledge the DNS data provided by Cristian Lalescu.
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