  A Multi-dipole line cusp configured Plasma Device (MPD) having six
electromagnets with embedded Vacoflux-50 as a core material has been operated
with a capability to experimentally control the field-free region, the radial
profile of magnetic field, and pole magnetic field by changing magnet current.
For the validation of multi-dipole line cusp magnetic field (MMF) configuration
in a 3-D geometry, a finite element simulation has been performed using COMSOL
software. This paper presents 3-D magnetic field simulation results of
multi-pole line cusp magnetic field configuration performed over the 1.2m
length and 40cm diameter chamber in the vacuum condition. The simulation
results show good agreement with the experimentally measured magnetic field
profile. The performed magnetic field simulation results clearly capture that
this configuration has full control over a null region (nearly field-free
region) as well is capable to change the magnetic field values and radial
variation of the magnetic field. Moreover, the magnetic field profiles over the
end cross-section of the device have been discussed.
