Directory:
    ${PENCIL_HOME}/samples/MHD-ABCforcing
SVN Id:
    $Id$
Maintainer:
    Axel Brandenburg <brandenb/nordita[dot]dk>
Added:
    27-Mar-2008
Status:
    succeeds since 27-Mar-2008
Recommended resolution:
    32x32x32 for nu=eta=1e-1 is used here and is fine. Somewhat smaller
    values would probably also work.
Comments:
    MHD with continuous ABC-flow driving. Unlike helical-MHDturb, which
    uses delta-correlated forcing that is added only at the end of each
    timestep, here the forcing is added on the rhs of the momentum eqn.
References:
    Sur, S., Subramanian, K., & Brandenburg, A.: 2007, ``Kinetic and
    magnetic alpha effects in nonlinear dynamo theory,'' Monthly Notices
    Roy. Astron. Soc. 376, 1238-1250 (astro-ph/0701001)