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arXiv · 1905.10365

The statistical properties of turbulence in the presence of a smart small-scale control

Michele Buzzicotti·Luca Biferale·Federico Toschi
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Abstract

By means of high-resolution numerical simulations, we compare the statistical properties of homogeneous and isotropic turbulence to those of the Navier-Stokes equation where small-scale vortex filaments are strongly depleted, thanks to a non-linear extra viscosity acting preferentially on high vorticity regions. We show that the presence of such smart small-scale drag can strongly reduce intermittency and non-Gaussian fluctuations. Our results pave the way towards a deeper understanding on the fundamental role of degrees of freedom in turbulence as well as on the impact of (pseudo)coherent structures on the statistical small-scale properties. Our work can be seen as a first attempt to develop smart-Lagrangian forcing/drag mechanisms to control turbulence.

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Michele Buzzicotti, Luca Biferale, Federico Toschi. 2019-05-24. The statistical properties of turbulence in the presence of a smart small-scale control. https://doi.org/10.1103/physrevlett.124.084504

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