Corpus ID: 210064487

Evolution of the turbulence interface in flows with and without stable stratification

  title={Evolution of the turbulence interface in flows with and without stable stratification},
  author={Marius M. Neamtu-Halic and Dominik Krug and Jean-Paul Mollicone and Maarten van Reeuwijk and George Haller and Markus Holzner},
  journal={arXiv: Fluid Dynamics},
The surface area of turbulent/non-turbulent interfaces (TNTIs) is continuously produced and destroyed via stretching and curvature/propagation effects. Here, the mechanisms responsible for TNTI area growth and destruction are investigated in a turbulent flow with and without stable stratification through the time evolution equation of the TNTI area. We show that both terms have broad distributions and may locally contribute to either production or destruction. On average, however, the area… Expand
Role of vortical structures for enstrophy and scalar transport in flows with and without stable stratification
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The coherent vortices in the proximity of the T/NT interface are preferentially aligned with the tangent to the T-NT interface and are responsible for the viscous dissipation of kinetic energy near theT/NT interfaces and to the characteristic shape of the enstrophy viscous diffusion observed at that location. Expand