DOI: https://doi.org/10.26089/NumMet.v21r215

Numerical modeling of statistical moments in a galactic dynamo problem with nonlinearity

Authors

  • D.A. Grachev
  • S.A. Elistratov

Keywords:

galactic dynamo
magnetic field
equations with random coefficients
statistical moment

Abstract

In this paper we consider a nonlinear modification of a stochastic model of the galactic dynamo in which the coefficient of turbulent diffusion is assumed to be a random process with renewal. It is shown that, in the case of small magnetic field strength, its statistical moments behave almost in the same manner as in the linear model; it is also shown that the intermittency effect exists. The characteristic time periods of moment stabilization are estimated when the magnetic field approaches its equilibrium. The numerical results obtained by averaging various samplings of its independent random implementations are compared.

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Published

2020-06-30

Issue

Vol. 21 (2020): Issue 2.

Section

Section 1. Numerical methods and applications

Author Biographies

D.A. Grachev

Lomonosov Moscow State University,
Faculty of Physics
• Researcher

S.A. Elistratov

Lomonosov Moscow State University,
Faculty of Physics
• Student

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