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arXiv · 1410.8263

A systematic bias in the calculation of spectral density from a 3D spatial grid

Rodion Stepanov·Franck Plunian·Mouloud Kessar·Guillaume Balarac
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Abstract

The energy spectral density $E(k)$, where $k$ is the spatial wave number, is a well-known diagnostic of homogeneous turbulence and magnetohydrodynamic turbulence. However in most of the curves plotted by different authors, some systematic kinks can be observed at $k=9$, $k=15$ and $k=19$. We claim that these kinks have no physical meaning, and are in fact the signature of the method which is used to estimate $E(k)$ from a 3D spatial grid. In this paper we give another method, in order to get rid of the spurious kinks and to estimate $E(k)$ much more accurately.

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Rodion Stepanov, Franck Plunian, Mouloud Kessar, Guillaume Balarac. 2014-10-30. A systematic bias in the calculation of spectral density from a 3D spatial grid. https://doi.org/10.1103/physreve.90.053309

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