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We report on the fourth phase of our study of slightly rotating accretionflows onto black holes. The main new element of this study is that we usedfully three dimensional (3-D) numerical simulations. We consider hydrodynamicsof inviscid accretion flows. We assume a spherically symmetric densitydistribution at the outer boundary, but brake the flow symmetry by introducinga small, latitude-dependent angular momentum. We also consider cases whereangular momentum at large radii is latitude- and azimuth-dependent. For thelatitude-dependent angular momentum, 3-D simulations confirm axisymmetricresults: the material that has too much angular momentum to be accreted forms athick torus near the equator. Consequently, accretion proceeds only through thepolar funnel, and the mass accretion rate through the funnel is constrained bythe size and shape of the torus, not by the outer conditions. In 3-Dsimulations, we found that the torus precesses, even for axisymmetricconditions at large radii. For the latitude and azimuth-dependent angularmomentum, the non-rotating gas near the equator can also significantly affectthe evolution of the rotating gas. In particular, it may prevent the formationof a proper torus (i.e. its closing, in the azimuthal direction). In suchmodels, the mass accretion rate is only slightly less than the correspondingBondi rate.

Nonaxisymmetric Effects in the Black Hole Accretion Inviscid Hydrodynamics: Formation and Evolution of a Tilted Torus