Related papers: The Shakura-Sunyaev Viscosity Prescription with Va…
We examine the evolution and influence of viscosity-induced diskoseismic modes in simulated black hole accretion disks. Understanding the origin and behavior of such oscillations will help us to evaluate their potential role in producing…
We present results from two-dimensional, general relativistic, viscous, radiation hydrodynamic numerical simulations of Shakura-Sunyaev thin disks accreting onto stellar mass Schwarzschild black holes. We consider cases on both the gas- and…
The Leray-$\alpha$ model reduces the range of active scales of the Navier-Stokes equations by smoothing the advective transport. Here we assess the potential of the Leray-$\alpha$ model in its standard formulation to simulate wall-bounded…
We study the dynamics of super-Eddington accretion flows by performing two-dimensional radiation-hydrodynamic simulations. Compared with previous works, in this paper we include the $T_{\theta\phi}$ component of the viscous stress and…
We investigate accretion onto a central star, with the size, rotation rate, and magnetic dipole of a young stellar object, to study the flow pattern (velocity and density) of the fluid within and outside of the disc. We perform resistive…
During the final growth phase of giant planets, accretion is thought to be controlled by a surrounding circumplanetary disk. Current astrophysical accretion disk models rely on hydromagnetic turbulence or gravitoturbulence as the source of…
We present nonlinear mean-field alpha-Omega dynamo simulations in spherical geometry with simplified profiles of kinematic alpha effect and shear. We take magnetic helicity evolution into account by solving a dynamical equation for the…
New three dimensional magnetohydrodynamic simulations of accretion disk dynamics in a pseudo-Newtonian Paczynski-Wiita potential are presented. These have finer resolution in the inner disk than any previously reported. Finer resolution…
Axisymmetric magnetorotational instability (MRI) in viscous accretion disks is investigated by linear analysis and two-dimensional nonlinear simulations. The linear growth of the viscous MRI is characterized by the Reynolds number defined…
A complete and detailed knowledge of the structure of the gaseous component in protoplanetary discs is essential to the study of dust evolution during the early phases of pre-planetesimal formation. The aim of this paper is to determine if…
Magnetically driven mass accretion in protoplanetary disks plays a crucial role in understanding disk evolution and planet formation. However, the $\alpha$ prescription lacks a direct connection to physical processes, and no systematic…
We use global magnetohydrodynamic simulations to study the influence of net vertical magnetic fields on the structure of geometrically thin ($H/r \approx 0.05$) accretion disks in the Newtonian limit. We consider initial mid-plane gas to…
Recent Atacama Large Millimeter and Submillimeter Array (ALMA) observations of the protoplanetary disk around the Herbig Ae star HD 163296 revealed three depleted dust gaps at 60, 100 and 160 au in the 1.3 mm continuum as well as CO…
We explore effects of the Shakura-Sunyaev alpha-viscosity on the dynamics and oscillations of slender tori. We start with a slow secular evolution of the torus. We show that the angular-momentum profile approaches the Keplerian one on the…
We use the Shaviv and Wehrse (1991) code to model the vertical structure and the emission properties of quiescent dwarf nova discs. We find that in the case of HT Cas the quiescent disc must be optically thin, in contradiction with the…
The structure of the boundary layer region between the disc and a comparatively slowly rotating star is studied using a causal prescription for viscosity. The vertically integrated viscous stress relaxes towards its equilibrium value on a…
We perform 3D radiation hydrodynamic local shearing box simulations to study the outcome of gravitational instability (GI) in optically thick Active Galactic Nuclei (AGN) accretion disks. GI develops when the Toomre parameter QT \leq 1, and…
We study the time evolution of a rotating, axisymmetric, viscous accretion flow around black holes using a grid based finite difference method. We use the Shakura-Sunyaev viscosity prescription. However, we compare with the results obtained…
We present the results of a 3D global magnetohydrodynamic (MHD) simulation of an AM CVn system that was aimed at exploring eccentricity growth in the accretion disc self-consistently from a first principles treatment of the MHD turbulence.…
The question of a purely hydrodynamic origin of turbulence in accretion disks is reexamined, on the basis of a large body of experimental and numerical evidence on various subcritical (i.e., linearly stable) hydrodynamic flows. One of the…