  We study a slightly rotating accretion flow onto a black hole, using the
fully three dimensional (3-D)numerical simulations. We consider hydrodynamics
of an inviscid flow, assuming a spherically symmetric density distribution at
the outer boundary and a small, latitude-dependent angular momentum. We
investigate the role of the adiabatic index and gas temperature, and the flow
behaviour due to non-axisymmetric effects. Our 3-D simulations confirm
axisymmetric results: the material that has too much angular momentum to be
accreted forms a thick torus near the equator and the mass accretion rate is
lower than the Bondi rate.
  In our previous study of the 3-D accretion flows, for gamma=5/3, we found
that the inner torus precessed, even for axisymmetric conditions at large
radii. The present study shows that the inner torus precesses also for other
values of the adiabatic index: gamma=4/3, 1.2 and 1.01. However, the time for
the precession to set increases with decreasing gamma. In particular, for
gamma=1.01 we find that depending on the outer boundary conditions, the torus
may shrink substantially due to the strong inflow of the non-rotating matter
and the precession will have insufficient time to develop. On the other hand,
if the torus is supplied by the continuous inflow of the rotating material from
the outer radii, its inner parts will eventually tilt and precess, as it was
for the larger gamma's.
