Characterization of velocity-gradient dynamics in incompressible turbulence using local streamline geometry

  title={Characterization of velocity-gradient dynamics in incompressible turbulence using local streamline geometry},
  author={Rishita Das and Sharath S. Girimaji},
  journal={Journal of Fluid Mechanics},
This study develops a comprehensive description of local streamline geometry and uses the resulting shape features to characterize velocity gradient ($\unicode[STIX]{x1D608}_{ij}=\unicode[STIX]{x2202}u_{i}/\unicode[STIX]{x2202}x_{j}$) dynamics. The local streamline geometric shape parameters and scale factor (size) are extracted from $\unicode[STIX]{x1D608}_{ij}$ by extending the linearized critical point analysis. In the present analysis, $\unicode[STIX]{x1D608}_{ij}$ is factorized into its… 

The effect of large-scale forcing on small-scale dynamics of incompressible turbulence

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The Schur decomposition of the velocity gradient tensor for turbulent flows

  • C. Keylock
  • Mathematics
    Journal of Fluid Mechanics
  • 2018
The velocity gradient tensor for turbulent flow contains crucial information on the topology of turbulence, vortex stretching and the dissipation of energy. A Schur decomposition of the velocity

Modern Geometries. A Gary W. Ostedt book 9780534351885

  • 1998

Statistical Fluid Mechanics, Volume II: Mechanics of Turbulence

  • 2013

On the Reynolds number dependence of velocity-gradient structure and dynamics

We seek to examine the changes in velocity-gradient structure (local streamline topology) and related dynamics as a function of Reynolds number ( $Re_{\unicode[STIX]{x1D706}}$ ). The analysis

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