Turbulence models and plane layer dynamos

Chris Jones ,  University of Exeter

Small-scale motions that significantly influence the dynamo mechanism cannot be numerically resolved.
Two approximate ways that have been suggested for incorporating these ``sub-grid scales" are investigated here:
the addition of hyperdiffusion and the application of Camassa-Holm-alpha theory.
These proposals were tested by comparing their consequences,
not only for marginal convection but also for finite amplitude dynamos, with corresponding 'exact' results .
 Plane layer models were studied because of their numerical advantages.