Using a specific solar null point reconnection case studied by
Masson et al (2009; ApJ 700, 559) we investigate the dependence of the
reconnection rate on boundary driving speed, numerical resolution,
type of resistivity (constant or numerical), and assumed stratification
(constant density or solar-like). The MHD simulations start out from a
potential magnetic field containing a null-point, obtained from a
SOHO magnetogram extrapolation approximately 8 hours before a
C-class flare was observed. The magnetic field is stressed with a
boundary motion pattern similar to the horizontal motions observed
by SOHO during the period preceding the flare. The general behavior
is nearly independent of driving speed and numerical resolution, and
is also very similar in stratified and unstratified models, provided only
that the boundary motions are slow enough.