Multiscale model of gradient evolution in turbulent flows.

  title={Multiscale model of gradient evolution in turbulent flows.},
  author={Luca Biferale and Laurent Chevillard and Charles Meneveau and Federico Toschi},
  journal={Physical review letters},
  volume={98 21},
A multiscale model for the evolution of the velocity gradient tensor in turbulence is proposed. The model couples "restricted Euler" (RE) dynamics describing gradient self-stretching with a cascade model allowing energy exchange between scales. We show that inclusion of the cascade process is sufficient to regularize the finite-time singularity of the RE dynamics. Also, the model retains geometrical features of real turbulence such as preferential alignments of vorticity and joint statistics of… 

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