  We performed 3D MHD calculations of stream accretion in cataclysmic variable
stars for which the white dwarf primary star possesses a strong and complex
magnetic field. These calculations are motivated by observations of polars;
cataclysmic variables containing white dwarfs with magnetic fields sufficiently
strong to prevent the formation of an accretion disk. So an accretion stream
flows from the L1 point and impacts directly onto one or more spots on the
surface of the white dwarf. Observations indicate that the white dwarf, in some
binaries, possesses a complex (non-dipolar) magnetic field. We perform
simulations of 10 polars or equivalently one asynchronous polar at 10 different
beat phases. Our models have an aligned dipole plus quadrupole magnetic field
centered on the white dwarf primary. We find that for a sufficiently strong
quadrupole component an accretion spot occurs near the magnetic equator for
slightly less than half of our simulations while a polar accretion zone is
active for most of the rest of the simulations. For one or two configurations;
accretion at the dominant polar region and at an equatorial zone occurs
simultaneously. These are the first 3D MHD calculations to confirm the
existence of complex magnetic fields in magnetic CVs. We conclude, that it
might be difficult observationally determine if the field is a pure dipole or
if it is complex for polars, but there will be indications for some systems.
Specifically, a complex magnetic field should be considered if the there is an
accretion zone near the white dwarf's spin equator (orbital plane) or if there
are two or more accretion regions that cannot be fit by a dipole magnetic
field. For asynchronous polars, magnetic field constraints are expected to be
substantially stronger, with clearer indicators of complex field geometry due
to changes in accretion flow structure as a function of spin-orbit beat phase.
