The effects of flux transport on interface dynamos

TL;DR

This paper investigates how simplified anisotropic flux transport mechanisms affect the efficiency and behavior of interface dynamos, highlighting the importance of transport profiles and boundary conditions.

Contribution

It introduces a simplified anisotropic flux transport model to study its impact on interface dynamo efficiency and wave frequency, emphasizing the role of transport profiles and boundary conditions.

Findings

Transport generally hinders dynamo onset and increases wave frequency.

There exists an optimal transport magnitude for maximum dynamo efficiency.

Boundary conditions significantly influence conclusions about flux transport effects.

Abstract

The operation of an interface dynamo (as has been suggested for the Sun and other stars with convective envelopes) relies crucially upon the effective transport of magnetic flux between two spatially disjoint generation regions. In the simplest models communication between the two regions is achieved solely by diffusion. Here we incorporate a highly simplified anisotropic transport mechanism in order to model the net effect of flux conveyance by magnetic pumping and by magnetic buoyancy. We investigate the influence of this mechanism on the efficiency of kinematic dynamo action. It is found that the effect of flux transport on the efficiency of the dynamo is dependent upon the spatial profile of the transport. Typically, transport hinders the onset of dynamo action and increases the frequency of the dynamo waves. However, in certain cases there exists a preferred magnitude of transport for which dynamo action is most efficient. Furthermore, we demonstrate the importance of the imposition of boundary conditions in drawing conclusions on the role of transport.