We examine the complex nonlinear flow-magnetic field dynamics in magneto-hydrodynamic (MHD) turbulence. Using direct numerical simulations (DNS), we investigate the dynamical interactions subject to the influence of a uniform applied background magnetic field. The initial magnetic and kinetic Reynolds numbers (based on Taylor microscale) are 45 and there are no initial magnetic field fluctuations. The sum total of turbulent magnetic and kinetic energies decays monotonically. With time, the turbulent magnetic fluctuations grow by extracting energy from velocity fluctuations. Expectedly, the distribution of energy between kinetic and magnetic fluctuations exhibits large periodic oscillations from the equipartition state due to Alfvén waves. We perform a detailed analysis of the flow-magnetic field coupling and posit a simple model for the energy interchange. Such dynamical analysis can provide the insight required for turbulence control and closure modeling strategies.
Characterization of Flow-Magnetic Field Interactions in Magneto-Hydrodynamic Turbulence
Contributed by the Design Engineering Division of ASME for publication in the Journal of Computational and Nonlinear Dynamics. Manuscript received January 4, 2012; final manuscript received December 12, 2012; published online January 25, 2013. Assoc. Editor: D. Dane Quinn.
- Views Icon Views
- Share Icon Share
- Cite Icon Cite
- Search Site
Richard, J. C., Kumar, G., Kalmár-Nagy, T., and Girimaji, S. S. (January 25, 2013). "Characterization of Flow-Magnetic Field Interactions in Magneto-Hydrodynamic Turbulence." ASME. J. Comput. Nonlinear Dynam. July 2013; 8(3): 031010. https://doi.org/10.1115/1.4023323
Download citation file:
- Ris (Zotero)
- Reference Manager