Oscillating advective accretion discs: structure and dynamical properties from the hydrodynamic simulations

We investigate the time evolution of two-dimensional sub-Keplerian transonic accretion flows onto black holes. Using boundary values derived from semi-analytical analysis, we simulate shocked accretion flows and focus on viscosity regimes that exhibit shock oscillations within the disc. By varying both viscosity and radiation cooling, we explore the dynamics of this configuration. Viscosity redistributes angular momentum, pushing the shock surface outward, while cooling reduces the temperature gradient, driving the shock inward. These processes ultimately affect the shock's stability and dynamics. We also evaluate the luminosity of our models, finding that post-shock oscillations lead to quasi-periodic oscillations (QPOs) across a wide frequency range in synthetic light curves for stellar-mass black hole binaries. Additionally, we observe that outflows are highly correlated with QPO frequencies. For spinning black holes, the outflows are more collimated and exhibit higher velocities