The Equivalence of the Lagrangian-Averaged Navier-Stokes- Model and the Rational LES model in Two Dimensions

  title={The Equivalence of the Lagrangian-Averaged Navier-Stokes- Model and the Rational LES model in Two Dimensions},
  author={Balasubramanya T. Nadiga and Freddy Bouchet},
  journal={arXiv: Fluid Dynamics},
In the Large Eddy Simulation (LES) framework for modeling a turbulent flow, when the large scale velocity field is defined by low-pass filtering the full velocity field, a Taylor series expansion of the full velocity field in terms of the large scale velocity field leads (at the leading order) to the nonlinear gradient model for the subfilter stresses. Motivated by the fact that while the nonlinear gradient model shows excellent a priori agreement in resolved simulations, the use of this model… 

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