The turbulence boundary of a temporal jet

  title={The turbulence boundary of a temporal jet},
  author={Maarten van Reeuwijk and Markus Holzner},
  journal={Journal of Fluid Mechanics},
  pages={254 - 275}
Abstract We examine the structure of the turbulence boundary of a temporal plane jet at $\mathit{Re}= 5000$ using statistics conditioned on the enstrophy. The data is obtained by direct numerical simulation and threshold values span 24 orders of magnitude, ranging from essentially irrotational fluid outside the jet to fully turbulent fluid in the jet core. We use two independent estimators for the local entrainment velocity ${v}_{n} $ based on the enstrophy budget. The data show clear evidence… 

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