Global MHD Simulations of Cylindrical Keplerian Disks

摘要: This paper presents a series of global three dimensional accretion disk simulations carried out in the cylindrical limit which vertical component gravitational field is neglected. The use pseudo-Newtonian potential to model main dynamical properties Schwarzschild metric. disks are initially constant density with Keplerian angular momentum distribution and contain weak toroidal or field. These reaffirm many conclusions previous local simulations. magnetorotational instability grows rapidly produces MHD turbulence significant Maxwell stress drives accretion. Tightly-wrapped low-$m$ spiral waves prominent. In some radial variations concentrate gas into rings, creating substantial spatial inhomogeneities. There nonzero at marginally stable orbit small decline specific inside last orbit. Detailed comparisons between used examine effects computational domain equation state. Simulations that begin fields have greater amplification higher ratios magnetic pressure compared those beginning fields. contrast MHD, hydrodynamics alone neither creates nor sustains turbulence.