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We present results of numerical simulation of inviscid thick accretion disksand wind flows around black holes. We use Smoothed Particle Hydrodynamics (SPH)technique for this purpose. Formation of thick disks are found to be precededby shock waves travelling away from the centrifugal barrier. For a large rangeof the parameter space, the travelling shock settles at a distance close to thelocation obtained by a one-and-a-half dimensional model of inviscid accretiondisks. Occasionally, it is observed that accretion processes are aided by theformation of oblique shock waves, particularly in the initial transient phase.The post-shock region (where infall velocity suddenly becomes very small)resembles that of the usual model of thick accretion disk discussed in theliterature, though they have considerable turbulence. The flow subsequentlybecomes supersonic before falling into the black hole. In a large number ofcases which we simulate, we find the formation of strong winds which are hotand subsonic when originated from the disk surface very close to the black holebut become supersonic within a few tens of the Schwarzschild radius of theblackhole. In the case of accretion of high angular momentum flow, very littleamount of matter is accreted directly onto the black hole. Most of the matteris, however, first squeezed to a small volume close to the black hole, andsubsequently expands and is expelled as a strong wind. It is quite possiblethat this expulsion of matter and the formation of cosmic radio jets is aidedby the shock heating in the inner parts of the accretion disks.Comment: LaTeX, 16 pages, Astrophysical Journal (in press

Simulation of thick accretion disks with standing shocks by smoothed particle hydrodynamics