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arXiv · 1005.0878

Non-locality of Hydrodynamic and Magnetohydrodynamic Turbulence

Jungyeon Cho
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Abstract

We compare non-locality of interactions between different scales in hydrodynamic (HD) turbulence and magnetohydrodynamic (MHD) turbulence in a strongly magnetized medium. We use 3-dimensional incompressible direct numerical simulations to evaluate non-locality of interactions. Our results show that non-locality in MHD turbulence is much more pronounced than that in HD turbulence. Roughly speaking, non-local interactions count for more than 10\% of total interactions in our MHD simulation on a grid of $512^3$ points. However, there is no evidence that non-local interactions are important in our HD simulation with the same numerical resolution. We briefly discuss how non-locality affects energy spectrum.

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Jungyeon Cho. 2010-05-06. Non-locality of Hydrodynamic and Magnetohydrodynamic Turbulence. https://doi.org/10.1088/0004-637x%2F725%2F2%2F1786

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