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Partial dust obscuration in active galactic nuclei (AGN) has been proposed asa potential explanation for some cases of AGN variability. The dust-gas mixturepresent in AGN torii is accelerated by radiation pressure leading to thelaunching of an AGN wind. Dust under these conditions has been shown to beunstable to a generic class of fast growing resonant drag instabilities (RDIs).We present the first set of numerical simulations of radiation driven outflowsthat include explicit dust dynamics in conditions resembling AGN winds anddiscuss the implications of the RDIs on the morphology of the AGN torus, AGNvariability, and the ability of the radiation to effectively launch a wind. Wefind that the RDIs rapidly develop reaching saturation at times much shorterthan the global timescales of the outflows, resulting in the formation offilamentary structure on box-size scales with strong dust clumping andsuper-Alfv\'enic velocity dispersions on micro-scales. This results in 10-20%fluctuations in dust opacity and gas column density, integrated along mockobserved lines-of-sight to the quasar accretion disk, over year to decadetimescales with a red-noise power spectrum which is commonly observed for AGN.Additionally, all our simulations show that the radiation is sufficientlycoupled to the dust-gas mixture launching highly super-sonic winds, whichentrain 70-90% of gas, with a factor of $\lesssim 3$ photon momentum lossrelative to the ideal case. Therefore, the RDIs could play an important role ingenerating the clumpy nature of AGN torii and driving AGN variabilityconsistent with observations.

Dust Dynamics in AGN Winds: A New Mechanism For Multiwavelength AGN Variability