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arXiv · 2104.13518

Dynamic Phase Alignment in Navier-Stokes Turbulence

Lucio M. Milanese·Nuno F. Loureiro·Stanislav Boldyrev
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Abstract

In Navier-Stokes turbulence, energy and helicity injected at large scales are subject to a joint direct cascade, with both quantities exhibiting a spectral scaling $\propto k^{-5/3}$. We demonstrate via direct numerical simulations that the two cascades are compatible due to the existence of a strong scale-dependent phase alignment between velocity and vorticity fluctuations, with the phase alignment angle scaling as $\cosα_k\propto k^{-1}$.

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Lucio M. Milanese, Nuno F. Loureiro, Stanislav Boldyrev. 2021-11-05. Dynamic Phase Alignment in Navier-Stokes Turbulence. https://doi.org/10.1103/physrevlett.127.274501

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