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arXiv · 0709.0628

Lagrangian Investigation of Two-Dimensional Decaying Turbulence

Michael Wilczek·Oliver Kamps·Rudolf Friedrich
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Abstract

We present a numerical investigation of two-dimensional decaying turbulence in the Lagrangian framework. Focusing on single particle statistics, we investigate Lagrangian trajectories in a freely evolving turbulent velocity field. The dynamical evolution of the tracer particles is strongly dominated by the emergence and evolution of coherent structures. For a statistical analysis we focus on the Lagrangian acceleration as a central quantity. For more geometrical aspects we investigate the curvature along the trajectories. We find strong signatures for self-similar universal behavior.

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Michael Wilczek, Oliver Kamps, Rudolf Friedrich. 2007-09-05. Lagrangian Investigation of Two-Dimensional Decaying Turbulence. https://doi.org/10.1016/j.physd.2008.01.013

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