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arXiv · 1802.00845

Periodic orbits in Large Eddy Simulation of Box Turbulence

Lennaert van Veen·Alberto Vela Martin·Genta Kawahara·Tatsuya Yasuda
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Abstract

We describe and compare two time-periodic flows embedded in Large Eddy Simulation (LES) of turbulence in a three-dimensional, periodic domain subject to constant external forcing. One of these flows models the regeneration of large-scale structures that was observed in this geometry by Yasuda et al. ({\sl Fluid Dyn. Res.} {\bf 46}, 061413, 2014), who used a smaller LES filter length and thus obtained a greater separation of scales of coherent motion. We speculate on the feasibility of modelling the regenerative dynamics with time-periodic solutions in such a flow, which may require novel techniques to deal with the extreme ill-conditioning of the associated boundary value problems.

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Lennaert van Veen, Alberto Vela Martin, Genta Kawahara, Tatsuya Yasuda. 2018-02-02. Periodic orbits in Large Eddy Simulation of Box Turbulence. https://doi.org/10.1088/1873-7005%2Faac7ec

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