Statistical Simulation of the Magnetorotational Dynamo

Squire, J.; Bhattacharjee, A.

doi:10.1103/PhysRevLett.114.085002

Title: Statistical Simulation of the Magnetorotational Dynamo

Full Record
Other Related Research

Authors:: Squire, J.; Bhattacharjee, A.

Publication Date:: Thu Feb 26 00:00:00 EST 2015

Sponsoring Org.:: USDOE

OSTI Identifier:: 1179941

Grant/Contract Number:: AC02-09CH11466

Resource Type:: Publisher's Accepted Manuscript

Journal Name:: Physical Review Letters

Additional Journal Information:: Journal Volume: 114; Journal Issue: 8; Journal ID: ISSN 0031-9007

Publisher:: American Physical Society

Country of Publication:: United States

Language:: English

Citation Formats


                    Squire, J., and Bhattacharjee, A. Statistical Simulation of the Magnetorotational Dynamo.  United States: N. p., 2015. 
Web.  doi:10.1103/PhysRevLett.114.085002.

Copy to clipboard


                    Squire, J., & Bhattacharjee, A. Statistical Simulation of the Magnetorotational Dynamo.  United States.  https://doi.org/10.1103/PhysRevLett.114.085002

Copy to clipboard


                    Squire, J., and Bhattacharjee, A. Thu .  
"Statistical Simulation of the Magnetorotational Dynamo".  United States.  https://doi.org/10.1103/PhysRevLett.114.085002.

Copy to clipboard


                    
@article{osti_1179941,

  title        = {Statistical Simulation of the Magnetorotational Dynamo},

  author       = {Squire, J. and Bhattacharjee, A.},

  abstractNote = {},

  doi          = {10.1103/PhysRevLett.114.085002},

  journal      = {Physical Review Letters},

  number       = 8,

  volume       = 114,

  place        = {United States},

  year         = {Thu Feb 26 00:00:00 EST 2015},

  month        = {Thu Feb 26 00:00:00 EST 2015}

}

Copy to clipboard

Journal Article:

Free Publicly Available Full Text

Accepted Manuscript (Publisher)

Publisher's Version of Record
https://doi.org/10.1103/PhysRevLett.114.085002

Other availability

Search WorldCat to find libraries that may hold this journal

Citation Metrics:

Cited by: 28 works

Citation information provided by
Web of Science

Save / Share:

Export Metadata

Save to My Library

Similar Records in DOE PAGES and OSTI.GOV collections:

Statistical simulation of the magnetorotational dynamo

Journal Article Squire, J. ; Bhattacharjee, A. - Physical Review letters

We analyze turbulence and dynamo induced by the magnetorotational instability (MRI) using quasi-linear statistical simulation methods. We find that homogenous turbulence is unstable to a large scale dynamo instability, which saturates to an inhomogenous equilibrium with a very strong dependence on the magnetic Prandtl number (Pm). Despite its enormously reduced nonlinearity, the quasi-linear model exhibits the same qualitative scaling of angular momentum transport with Pm as fully nonlinear turbulence. This demonstrates the relationship of recent convergence problems to the large scale dynamo and suggests possible methods for studying astrophysically relevant regimes at very low or high Pm.
Full Text Available
Statistical Simulation of the Magnetorotational Dynamo

Journal Article Squire, Jonathan ; Bhattacharjee, Amitava - Physical Review Letters

Turbulence and dynamo induced by the magnetorotational instability (MRI) are analyzed using quasilinear statistical simulation methods. It is found that homogenous turbulence is unstable to a large-scale dynamo instability, which saturates to an inhomogenous equilibrium with a strong dependence on the magnetic Prandtl number (Pm). Despite its enormously reduced nonlinearity, the dependence of the angular momentum transport on Pm in the quasilinear model is qualitatively similar to that of nonlinear MRI turbulence. This demonstrates the importance of the large-scale dynamo and suggests how dramatically simplified models may be used to gain insight into the astrophysically relevant regimes of very lowmore » or high Pm.« less
https://doi.org/10.1103/PhysRevLett.114.085002

Full Text Available
Global Simulations of Dynamo and Magnetorotational Instability in Madison Plasma Experiments and Astrophysical Disks

Technical Report Ebrahimi, Fatima

Large-scale magnetic fields have been observed in widely different types of astrophysical objects. These magnetic fields are believed to be caused by the so-called dynamo effect. Could a large-scale magnetic field grow out of turbulence (i.e. the alpha dynamo effect)? How could the topological properties and the complexity of magnetic field as a global quantity, the so called magnetic helicity, be important in the dynamo effect? In addition to understanding the dynamo mechanism in astrophysical accretion disks, anomalous angular momentum transport has also been a longstanding problem in accretion disks and laboratory plasmas. To investigate both dynamo and momentum transport,more »« less
https://doi.org/10.2172/1177153

Full Text Available
Large-scale dynamo action precedes turbulence in shearing box simulations of the magnetorotational instability

Journal Article Bhat, Pallavi ; Ebrahimi, Fatima ; Blackman, Eric G. - Monthly Notices of the Royal Astronomical Society

Here, we study the dynamo generation (exponential growth) of large-scale (planar averaged) fields in unstratified shearing box simulations of the magnetorotational instability (MRI). In contrast to previous studies restricted to horizontal (x–y) averaging, we also demonstrate the presence of large-scale fields when vertical (y–z) averaging is employed instead. By computing space–time planar averaged fields and power spectra, we find large-scale dynamo action in the early MRI growth phase – a previously unidentified feature. Non-axisymmetric linear MRI modes with low horizontal wavenumbers and vertical wavenumbers near that of expected maximal growth, amplify the large-scale fields exponentially before turbulence and high wavenumbermore »« less
Cited by 17
https://doi.org/10.1093/mnras/stw1619

Full Text Available
Simulations of Dynamo and Magnetorotational Instability in Madison Plasma Experiments and Astrophysical Disks

Technical Report Ebrahimi, Fatima

Magnetic fields are observed to exist on all scales in many astrophysical sources such as stars, galaxies, and accretion discs. Understanding the origin of large scale magnetic fields, whereby the field emerges on spatial scales large compared to the fluctuations, has been a particularly long standing challenge. Our physics objective are: 1) what are the minimum ingredients for large-scale dynamo growth? 2) could a large-scale magnetic field grow out of turbulence and sustained despite the presence of dissipation? These questions are fundamental for understanding the large-scale dynamo in both laboratory and astrophysical plasmas. Here, we report major new findings inmore »« less
https://doi.org/10.2172/1422354

Full Text Available

Similar Records