Lack of universality in decaying magnetohydrodynamic turbulence
Using computations of three-dimensional magnetohydrodynamic (MHD) turbulence with a Taylor-Green flow, whose inherent time-independent symmetries are implemented numerically, and in the absence of either a forcing function or an imposed uniform magnetic field, we show that three different inertial r...
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Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_15393755_v81_n1_p_Lee http://hdl.handle.net/20.500.12110/paper_15393755_v81_n1_p_Lee |
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paper:paper_15393755_v81_n1_p_Lee2023-06-08T16:20:46Z Lack of universality in decaying magnetohydrodynamic turbulence Mininni, Pablo Daniel Characteristic time Computational grids Correlation time Energy spectra Forcing function Forcing terms Magnetic Prandtl numbers Magnetohydrodynamic turbulence MHD turbulence Non-linear dynamics Taylor-Green flow Taylor-Reynolds number Magnetic fields Reynolds number Spectroscopy Turbulence Magnetohydrodynamics Using computations of three-dimensional magnetohydrodynamic (MHD) turbulence with a Taylor-Green flow, whose inherent time-independent symmetries are implemented numerically, and in the absence of either a forcing function or an imposed uniform magnetic field, we show that three different inertial ranges for the energy spectrum may emerge for three different initial magnetic fields, the selecting parameter being the ratio of nonlinear eddy to Alfvén time. Equivalent computational grids range from 1283 to 20483 points with a unit magnetic Prandtl number and a Taylor Reynolds number of up to 1500 at the peak of dissipation. We also show a convergence of our results with Reynolds number. Our study is consistent with previous findings of a variety of energy spectra in MHD turbulence by studies performed in the presence of both a forcing term with a given correlation time and a strong, uniform magnetic field. However, in contrast to the previous studies, here the ratio of characteristic time scales can only be ascribed to the intrinsic nonlinear dynamics of the paradigmatic flows under study. © 2010 The American Physical Society. Fil:Mininni, P.D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2010 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_15393755_v81_n1_p_Lee http://hdl.handle.net/20.500.12110/paper_15393755_v81_n1_p_Lee |
institution |
Universidad de Buenos Aires |
institution_str |
I-28 |
repository_str |
R-134 |
collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
topic |
Characteristic time Computational grids Correlation time Energy spectra Forcing function Forcing terms Magnetic Prandtl numbers Magnetohydrodynamic turbulence MHD turbulence Non-linear dynamics Taylor-Green flow Taylor-Reynolds number Magnetic fields Reynolds number Spectroscopy Turbulence Magnetohydrodynamics |
spellingShingle |
Characteristic time Computational grids Correlation time Energy spectra Forcing function Forcing terms Magnetic Prandtl numbers Magnetohydrodynamic turbulence MHD turbulence Non-linear dynamics Taylor-Green flow Taylor-Reynolds number Magnetic fields Reynolds number Spectroscopy Turbulence Magnetohydrodynamics Mininni, Pablo Daniel Lack of universality in decaying magnetohydrodynamic turbulence |
topic_facet |
Characteristic time Computational grids Correlation time Energy spectra Forcing function Forcing terms Magnetic Prandtl numbers Magnetohydrodynamic turbulence MHD turbulence Non-linear dynamics Taylor-Green flow Taylor-Reynolds number Magnetic fields Reynolds number Spectroscopy Turbulence Magnetohydrodynamics |
description |
Using computations of three-dimensional magnetohydrodynamic (MHD) turbulence with a Taylor-Green flow, whose inherent time-independent symmetries are implemented numerically, and in the absence of either a forcing function or an imposed uniform magnetic field, we show that three different inertial ranges for the energy spectrum may emerge for three different initial magnetic fields, the selecting parameter being the ratio of nonlinear eddy to Alfvén time. Equivalent computational grids range from 1283 to 20483 points with a unit magnetic Prandtl number and a Taylor Reynolds number of up to 1500 at the peak of dissipation. We also show a convergence of our results with Reynolds number. Our study is consistent with previous findings of a variety of energy spectra in MHD turbulence by studies performed in the presence of both a forcing term with a given correlation time and a strong, uniform magnetic field. However, in contrast to the previous studies, here the ratio of characteristic time scales can only be ascribed to the intrinsic nonlinear dynamics of the paradigmatic flows under study. © 2010 The American Physical Society. |
author |
Mininni, Pablo Daniel |
author_facet |
Mininni, Pablo Daniel |
author_sort |
Mininni, Pablo Daniel |
title |
Lack of universality in decaying magnetohydrodynamic turbulence |
title_short |
Lack of universality in decaying magnetohydrodynamic turbulence |
title_full |
Lack of universality in decaying magnetohydrodynamic turbulence |
title_fullStr |
Lack of universality in decaying magnetohydrodynamic turbulence |
title_full_unstemmed |
Lack of universality in decaying magnetohydrodynamic turbulence |
title_sort |
lack of universality in decaying magnetohydrodynamic turbulence |
publishDate |
2010 |
url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_15393755_v81_n1_p_Lee http://hdl.handle.net/20.500.12110/paper_15393755_v81_n1_p_Lee |
work_keys_str_mv |
AT mininnipablodaniel lackofuniversalityindecayingmagnetohydrodynamicturbulence |
_version_ |
1768545344741703680 |