Contour plot of velocity contours evaluated in Boyer-Lindquist coordinates for a uniform supersonic flow past a non-spinning black hole with flow parameters given by model UA1, evaluated at time t = 300M. The stagnation point is marked.

Contour plot of velocity for a supersonic flow with density perturbed by ϵ_ρ = 0.2 past a black hole with spin a = 0.9 and flow parameters given by model UA1, evaluated at time t = 400M, with the axes in units of M.

Accretion regions for two supersonic models based on UA1. The solid line shows the accretion region for a = 0, ϵ_ρ = 0, and the dashed line shows the accretion region for a = 0.9, ϵ_ρ = 0.2.

Mass accretion rate against density perturbation for different spins. The wind direction is parallel to the equatorial plane of the black hole in all cases.

Mass accretion rates against density perturbation. The labels refer to the angle between the equatorial plane and the wind direction. a) Spin a = 0.5; b) Spin a = 0.9.

Shock angles against density perturbation, varying the spin of the black hole. The wind direction is in the equatorial plane of the black hole in all cases.

Shock-cone angles against density perturbation. The angles are all taken in the plane containing the wind direction and the y-axis. The data points above and below the axis correspond to the shock-angles above and below the wind-direction axis. The labels correspond to the angle between the equatorial plane of the black hole and the wind direction. a) Spin a = 0.5; b) Spin a = 0.9.