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arXiv · 1608.01261

The turbulence velocity gradient tensor formed additively by normal and non-normal tensors

Christopher J. Keylock
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Abstract

We decompose the velocity gradient tensor for turbulence into normal and non-normal parts, and condition our analysis on the strain eigenvector alignments between these tensors. We identify states that always enhance, and always counteract the axisymmetric expansion state, and give a rationale for decomposing the production balance term into its constituents: complex behavior arises when the dominant strain alignments involve the non-normal tensor. Finally, we develop a topological analysis framework where mathematical bounds on two of the three variables leads to an analysis in two planes.

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Christopher J. Keylock. 2016-08-03. The turbulence velocity gradient tensor formed additively by normal and non-normal tensors. https://doi.org/10.1103/physrevfluids.2.084607

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