E-Print Archive

There are 4499 abstracts currently viewable.


Search:

Advanced Search
Options
Main Page Add New E-Print Submitter
Information
Feedback
News Help/FAQ About Preferences
Manage Key Phrase
Notification
Magnetic Prandtl number dependence of the kinetic-to-magnetic dissipation ratio View all abstracts by submitter

Axel Brandenburg   Submitted: 2014-07-30 00:01

Using direct numerical simulations of three-dimensional hydromagnetic turbulence, either with helical or non-helical forcing, we show that the ratio of kinetic-to-magnetic energy dissipation always increases with the magnetic Prandtl number, i.e., the ratio of kinematic viscosity to magnetic diffusivity. This dependence can always be approximated by a power law, but the exponent is not the same in all cases. For non-helical turbulence, the exponent is around 1/3, while for helical turbulence it is between 0.6 and 2/3. In the statistically steady state, the rate of the energy conversion from kinetic into magnetic by the dynamo must be equal to the Joule dissipation rate. We emphasize that for both small-scale and large-scale dynamos, the efficiency of energy conversion depends sensitively on the magnetic Prandtl number, and thus on the microphysical dissipation process. To understand this behavior, we also study shell models of turbulence and one-dimensional passive and active scalar models. We conclude that the magnetic Prandtl number dependence is qualitatively best reproduced in the one-dimensional model as a result of dissipation via localized Alfvén kinks.

Authors: Axel Brandenburg
Projects: None

Publication Status: Astrophys. J. 791, 12 (2014)
Last Modified: 2014-07-30 15:22
Go to main E-Print page  Coronal Loops: Observations and Modeling of Confined Plasma  A Systematic Approach to the Reconstruction of Saturated SDO/AIA Images  Edit Entry  Download Preprint  Submitter's Homepage Delete Entry 

Key
Go to main E-Print pageGo to main E-Print page.
Previous AbstractPrevious Abstract.
Next AbstractNext Abstract.
Download PreprintDownload Preprint.
Submitter's HomepageSubmitters Homepage.
Edit EntryEdit Entry.
View All Abstracts By SubmitterView all abstracts by submitter.
Delete AbstractDelete abstract.

Latest Entries
Small-scale solar jet formation and their associated waves and instabilities
Invited Review: Short-term Variability with the Observations from the Helioseismic and Magnetic Imager (HMI) Onboard the Solar Dynamics Observatory (SDO): Insights into Flare Magnetism
A first look at the submillimeter Sun with ALMA
Data-driven modeling of solar coronal magnetic field evolution and eruptions
Properties and Energetics of Magnetic Reconnection: I. Evolution of Flare Ribbons
A new look at the frequency-dependent damping of slow-mode waves in the solar corona
What determines active region coronal plasma composition?
Characteristics and evolution of sheath and leading edge structures of interplanetary coronal mass ejections in the inner heliosphere based on Helios and Parker Solar Probe observations
Slow magnetoacoustic oscillations in stellar coronal loops
Kink Oscillation of a Flux Rope During a Failed Solar Eruption
A publicly available multi-observatory data set of an enhanced network patch from the Photosphere
Type IV Radio Bursts and Associated Active Regions in the Sunspot Cycle 24
Theory of Fluid Instabilities in Partially Ionized Plasmas: An Overview
Quasiperiodic Energy Release and Jets at the Base of Solar Coronal Plumes
The Coupling of an EUV Coronal Wave and Ion Acceleration in a Fermi-LAT Behind-the-Limb Solar Flare
Reconciling Power Law Slopes in Solar Flare and Nanoflare Size Distributions
A Model of Homologous Confined and Ejective Eruptions Involving Kink Instability and Flux Cancellation
Detection of stellar-like abundance anomalies in the slow solar wind
Magnetosheath jet occurrence rate in relation to CMEs and SIRs
Microwave Perspective on Magnetic Breakout Eruption

Related Pages
MSU Solar Physics.
Max Millennium Science Mail Archive.
Max Millennium Message of the Day Mail Archive.
Max Millennium Flare Catalog

Archive Maintainer
Alisdair Davey



© 2000-2020 Solar Physics Group - Montana State University