Abstract

Turbulence has a profound impact on the evolution of gas and dust in protoplanetary disks (PPDs), from driving the collisions and the diffusion of dust grains, to the concentration of pebbles in giant vortices, thus, facilitating planetesimal formation. The Vertical Shear Instability (VSI) is a hydrodynamic mechanism, operating in PPDs if the local rate of thermal relaxation is high enough. Previous studies of the VSI have, however, relied on the assumption of constant cooling rates, or neglected the finite coupling time between the gas particles and the dust grains. Here, I present the results of hydrodynamic simulations of PPDs with the PLUTO code that include a more realistic thermal relaxation prescription. This enables us to study the turbulence and flow structure formation caused by VSI in the optically thick and optically thin parts of the disk under consideration of the thermal dust-gas coupling.