Relativistic wind accretion onto a rapidly rotating Kerr black hole (a=0.999 M) in Kerr-Schild coordinates (left panel).
The effects of the black hole spin on the flow morphology are confined to the inner regions of the black hole potential well. Within this region the black hole angular momentum drags the flow around. The transformation to Boyer-Lindquist coordinates (right panel) induces a noticeable wrapping of the shock around the central hole. Actually it would wrap infinitely many times before ever reaching the horizon.