Phenomenology of turbulent dynamo growth and saturation
نویسنده
چکیده
With a non local shell model of magnetohydrodynamic turbulence we investigate numerically the turbulent dynamo action for low and high magnetic Prandtl numbers (Pm). The results obtained in the kinematic regime and along the way to dynamo saturation are understood in terms of a phenomenological approach based on the local (Pm ≪ 1) or non local (Pm ≫ 1) nature of the energy transfers. In both cases the magnetic energy grows at small scale and saturates as an inverse “ cascade ”. Subject headings: MHD, turbulence, methods: numerical, magnetic fields, plasmas
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