Self-consistent turbulent dynamo modeling of reversed field pinches and planetary magnetic fields

Turbulent dynamo modeling in a rotating frame is performed to enable studies of reversed field pinches of fusion plasma and planetary magnetic fields. The Reynolds stresses, turbulent electromotive force, and other important correlation functions, which appear in the equations for the mean velocity and magnetic field, are modeled using the mean fields and four bulk turbulence quantities (the magnetohydrodynamic turbulent energy, its dissipation rate, the cross helicity, and the residual helicity). Four equations for those bulk quantities are combined with the mean-field equations to lead to a self-consistent dynamo model. Specifically, the importance of the cross-helicity effect is pointed out. This model shows that the equilibrium state of reversed field pinches of plasma is a neutral state under the condition of vanishing cross helicity. The relevance to the study of the Earth's and other planetary magnetic fields is discussed