Optimal thermalization in a shell model of homogeneous turbulence

@article{Thalabard2015OptimalTI,
  title={Optimal thermalization in a shell model of homogeneous turbulence},
  author={Simon Thalabard and Bruce Turkington},
  journal={arXiv: Fluid Dynamics},
  year={2015}
}
We investigate the turbulence-induced dissipation of the large scales in a statistically homogeneous flow using an "optimal closure," which one of us (BT) has recently exposed in the context of Hamiltonian dynamics. This statistical closure employs a Gaussian model for the turbulent scales, with corresponding vanishing third cumulant, and yet it captures an intrinsic damping. The key to this apparent paradox lies in a clear distinction between true ensemble averages and their proxies, most… 

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