Coupling of mean-field equation and shell model of turbulence in the context of galactic dynamo problem

Abstract

A model of the galactic dynamo has been proposed. It includes the equation of large-scale magnetic field induction written in terms of alpha-omega dynamo approximation and the shell model of magnetohydrodynamic turbulence, which allows evaluation of the turbulent transfer coefficients entering in the mean field equation. Although both models have been studied extensively, their simultaneous usage poses new questions concerning a correct description of the interaction between large-scale and small-scale fields. In this work coupling of the models has been made with the observance of all laws of conservation of the of the ideal magnetic hydrodynamics. As an example, several numerical simulations of the magnetic field dynamics have been carried out and the role of separate mechanisms of the large-scale field -turbulence interaction has been shown.