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This work presents a detailed analysis of the overall flow structure andunique features of the inner region of the tilted disk simulations described inFragile et al. (2007). The primary new feature identified in the main disk bodyis a latitude-dependent radial epicyclic motion driven by pressure gradientsattributable to the gravitomagnetic warping of the disk. The induced motion ofthe gas is coherent over the scale of the entire disk and is fast enough thatit could be observable in features such as relativistic iron lines. Theeccentricity of the associated fluid element trajectories increases withdecreasing radius, leading to a crowding of orbit trajectories near theirapocenters. This results in a local density enhancement akin to a compression.These compressions are sufficiently strong to produce a pair of weak shocks inthe vicinity of the black hole. These shocks are roughly aligned with theline-of-nodes between the black-hole symmetry plane and disk midplane, with oneshock above the line-of-nodes on one side of the black hole and the other belowon the opposite side. These shocks enhance angular momentum transport andenergy dissipation near the hole, forcing some material to plunge toward theblack hole from well outside the innermost stable circular orbit. A new,extended simulation, which was evolved for more than a full disk precessionperiod, allows us to confirm that these shocks and the previously identified``plunging streams'' precess with the disk in such a way as to remain alignedrelative to the line-of-nodes, as expected based on our physical understandingof these phenomena. Such a precessing structure would likely present a strongquasi-periodic signal.

Epicyclic Motions and Standing Shocks in Numerically Simulated Tilted Black-Hole Accretion Disks