AGN obscuration through dusty infrared dominated flows. II.   Multidimensional, radiation-hydrodynamics modeling
  We explore a detailed model in which the active galactic nucleus (AGN) obscuration results from the extinction of AGN radiation in a global flow driven by the pressure of infrared radiation on dust grains. We assume that external illumination by UV and soft X-rays of the dusty gas located at approximately 1pc away from the supermassive black hole is followed by a conversion of such radiation into IR. Using 2.5D, time-dependent radiation hydrodynamics simulations in a flux-limited diffusion approximation we find that the external illumination can support a geometrically thick obscuration via outflows driven by infrared radiation pressure in AGN with luminosities greater than $0.05\, L_{\rm edd}$ and Compton optical depth, $\tau_{\rm T}\gtrsim 1$. 
A. Dorodnitsyn, T. Kallman, G. S. Bisnovatyi-Kogan
astro-ph.HE