# 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…

## 7 Citations

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The topology of the local flow in vaporizing forced homogeneous isotropic turbulent two-phase flows is investigated and it is found that the joint probability density functions of the second and third invariants have classical shapes in all carrier-gas regions but gradually change as they approach the carrier-liquid interface.

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Abstract The local streamline topology classification method of Chong et al. (Phys. Fluids A: Fluid Dyn., vol. 2, no. 5, 1990, pp. 765–777) is adapted and extended to describe the geometry of…

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Turbulence small-scale behavior has been commonly investigated in literature by decomposing the velocity-gradient tensor (Aij) into the symmetric strain-rate (Sij) and anti-symmetric rotation-rate…

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