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

@article{Das2020CharacterizationOV,
  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},
  year={2020},
  volume={895}
}
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… 

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