Magnetic field evolution in simulations with Euler potentials

Details Magnetic field evolution in simulations with Euler potentials Magnetic field evolution in simulations with Euler potentials

2009-07-12

arxiv.org/abs/0907.1906v2

Mon. Not. R. Astron. Soc. 401, 347-354 (2010)

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

8 pages, 10 figures, MNRAS, accepted

Scientific paper

10.1111/j.1365-2966.2009.15640.x

Using two- and three-dimensional hydromagnetic simulations for a range of different flows, including laminar and turbulent ones, it is shown that solutions expressing the field in terms of Euler potentials (EP) are in general incorrect if the EP are evolved with an artificial diffusion term. In three dimensions, standard methods using the magnetic vector potential are found to permit dynamo action when the EP give decaying solutions. With an imposed field, the EP method yields excessive power at small scales. This effect is more exaggerated in the dynamic case, suggesting an unrealistically reduced feedback from the Lorentz force. The EP approach agrees with standard methods only at early times when magnetic diffusivity did not have time to act. It is demonstrated that the usage of EP with even a small artificial magnetic diffusivity does not converge to a proper solution of hydromagnetic turbulence. The source of this disagreement is not connected with magnetic helicity or the three-dimensionality of the magnetic field, but is simply due to the fact that the nonlinear representation of the magnetic field in terms of EP that depend on the same coordinates is incompatible with the linear diffusion operator in the induction equation.

Affiliated with

Also associated with

No associations

Rating

Magnetic field evolution in simulations with Euler potentials does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Magnetic field evolution in simulations with Euler potentials, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Magnetic field evolution in simulations with Euler potentials will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-593159