Influence of Large-scale Field Structures on the Scaling Anisotropy in 3D MHD Turbulence
- 1 October 2021
- journal article
- research article
- Published by American Astronomical Society in The Astrophysical Journal
- Vol. 920 (1), 14
- https://doi.org/10.3847/1538-4357/ac1790
Abstract
Magnetohydrodynamic (MHD) turbulence is revealed to have scaling anisotropy based on structure function calculations. Recent studies on solar wind turbulence found that the scaling anisotropy disappears when removing large-scale field structures. This finding raises questions as to whether numerical MHD turbulences have large-scale field structures. How do these structures affect the scaling anisotropy therein? Here we investigate these questions with a driven compressible three-dimensional MHD turbulence. We introduce a new method to check how the random stationarity condition is satisfied. We find for the first time in the numerical MHD turbulence that the large-scale field structures destroy the random stationarity of the local fields and make samplings nonparallel to the instantaneous fields be calculated as apparent parallel samplings. This mixture makes statistical calculations show anisotropic scaling of the turbulence. When we select only the random stationary data intervals, the statistical results show an isotropic nature. We also find that among the large-scale field structures, one-third are tangential discontinuities (TDs), one-third are rotational discontinuities (RDs), and the rest are EDs (either TD or RD). These results show that the large-scale structures in the numerical MHD turbulence have important influence on the structure function analysis.Funding Information
- National Natural Science Foundation of China (41974171)
- China Postdoctoral Science Foundation (2020M680204, BX2021006)
This publication has 51 references indexed in Scilit:
- The Solar Wind as a Turbulence LaboratoryLiving Reviews in Solar Physics, 2013
- OBSERVATIONS OF ANISOTROPIC SCALING OF SOLAR WIND TURBULENCEThe Astrophysical Journal Letters, 2010
- STATISTICAL ANALYSIS OF DISCONTINUITIES IN SOLAR WIND ACE DATA AND COMPARISON WITH INTERMITTENT MHD TURBULENCEThe Astrophysical Journal, 2009
- Intermittent MHD structures and classical discontinuitiesGeophysical Research Letters, 2008
- Spectrum of Magnetohydrodynamic TurbulencePhysical Review Letters, 2006
- Spectral Energy Dynamics in Magnetohydrodynamic TurbulencePhysical Review Letters, 2005
- Statistical anisotropy of magnetohydrodynamic turbulencePhysical Review E, 2003
- Simulations of Incompressible Magnetohydrodynamic TurbulenceThe Astrophysical Journal, 2001
- Toward a theory of interstellar turbulence. 2: Strong alfvenic turbulenceThe Astrophysical Journal, 1995
- Low-FrequencyNoise in the Interplanetary Magnetic FieldPhysical Review Letters, 1986