  We simulate shock-free and shocked viscous accretion flow onto a black hole
in a two dimensional cylindrical geometry, where initial conditions were chosen
from analytical solutions. The simulation code used the Lagrangian Total
Variation Diminishing (LTVD) and remap routine, which enabled us to attain high
accuracy in capturing shocks and to handle the angular momentum distribution
correctly. Inviscid shock-free accretion disk solution produced a thick disk
structure, while the viscous shock-free solution attained a Bondi-like
structure, but in either case, no jet activity nor any QPO-like activity
developed. The steady state shocked solution in the inviscid, as well as, in
the viscous regime, matched theoretical predictions well. However, increasing
viscosity renders the accretion shock unstable. Large amplitude shock
oscillation is accompanied by intermittent, transient inner multiple shocks.
Such oscillation of the inner part of disk is interpreted as the source of QPO
in hard X-rays observed in micro-quasars. Strong shock oscillation induces
strong episodic jet emission. The jets also showed existence of shocks, which
are produced as one shell hits the preceding one. The periodicity of jets and
shock oscillation were similar. The jets for higher viscosity parameter are
evidently stronger and faster.
