http://arxiv.org/abs/1802.08125
A toy model of the post-shock region of core-collapse supernovae is used to study the non-linear development of turbulent motions driven by convection in the presence of advection. Our numerical simulations indicate that buoyant perturbations of density are able to trigger self-sustained convection only when the instability is not linearly stabilized by advection. Large amplitude perturbations produced by strong shock oscillations or combustion inhomogeneities before the collapse of the progenitor are efficiently shredded through phase mixing and generate a turbulent cascade. Our model enables us to investigate several physical arguments that had been proposed to explain the impact of the dimensionality on the onset of explosions in global simulations of core-collapse supernovae. In three-dimensional simulations, we find that turbulent mixing and dissipation of the kinetic energy produce a significant increase of the heating which is barely seen in our two-dimensional models. These results suggest that the three-dimensional nature of convection may ease the onset of the explosion. Increasing the numerical resolution is found to be mostly promising to support explosions in 3D simulations that contain large amplitude perturbations.
R. Kazeroni, B. Krueger, J. Guilet, et. al.
Fri, 23 Feb 18
45/64
Comments: 23 pages, 18 figures, submitted to MNRAS