How do Dynamos Saturate ?

نویسندگان

  • FAUSTO CATTANEO
  • STEVEN M. TOBIAS
چکیده

In order better to understand how dynamo systems saturate, we study the kinematic dynamo properties of velocity fields that arise from nonlinearly saturated dynamos. The technique is implemented by solving concurrently, in addition to the momentum equation, two induction equations, one for the actual magnetic field, and one for an independent passive field. We apply this technique to two illustrative examples: convectively driven turbulence, and turbulence represented by a shell model. In all cases we find that the velocity remains an efficient kinematic dynamo even after nonlinear saturation occurs. We discuss the implications to the process of dynamo saturation.

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تاریخ انتشار 2008