Mean-Field Electromotive Force in Magnetohydrodynamic Turbulence
In a turbulent magnetized plasma, the electromotive force is the statistically averaged cross product of the fluctuating flow velocity and fluctuating magnetic field, E = <deltaU x deltaB>, an effective large-scale electric field that closes the mean-field MHD induction equation. Learners study how this term decomposes into turbulent transport coefficients (the alpha effect that amplifies large-scale magnetic fields, the beta effect of turbulent diffusion, and the cross-helicity gamma effect) and how it is measured from spacecraft data in the solar wind.
Electromotive field in space and astrophysical plasmas
The electromotive field (EMF) in a magnetized plasma is the statistically averaged cross product of the fluctuating flow velocity and the fluctuating magnetic field, E = <deltaU x deltaB>, an effecti…