  This paper presents a numerical investigation of isolated filament dynamics
in a simulation geometry representative of the scrape-off layer (SOL) of the
Mega Amp Spherical Tokamak (MAST) previously studied in [N.R.Walkden et.al,
Plasma Phys. Control. Fusion, 55 (2013) 105005]. This paper focuses on the
evolution of filament cross-sections at the outboard midplane and investigates
the scaling of the centre of mass velocity of the filament cross-section with
filament width and electron temperature. By decoupling the vorticity equation
into even and odd parity components about the centre of the filament in the
bi-normal direction parallel density gradients are shown to drive large
velocities in the bi-normal (approximately poloidal) direction which scale
linearly with electron temperature. In this respect increasing the electron
temperature causes a departure of the filament dynamics from 2D behaviours.
Despite the strong impact of 3D effects the radial motion of the filament is
shown to be relatively well predicted by 2D scalings. The radial velocity is
found to scale positively with both electron temperature and cross-sectional
width, suggesting an inertially limited nature. Comparison with the two-region
model [J. R. Myra et.al, Phys.Plasmas, 13 (2006) 112502] achieves reasonable
agreement when using a corrected parallel connection length due to the neglect
of diamagnetic currents driven in the divertor region of the filament. Analysis
of the transport of particles due to the motion of the filament shows that the
background temperature has a weak overall effect on the radial particle flux
whilst the filament width has a strong effect.
