Impact of Local Pressure Enhancements on Dust Concentration inTurbulent Protoplanetary Discs

Abstract

We investigate the evolution of dust and gas in the vicinity of local pressure enhancements (pressure bumps) in a protoplanetary disc (PPD) with turbulence due to the Vertical Shear Instability (VSI). We perform global 2D axisymmetric and 3D simulations of dust and gas for a range of values for Z (ratio of dust-to-gas (d/g) surface mass densities or metallicity), particle Stokes numbers tau, and pressure bump amplitude A. Dust feedback onto the gas is included. For the first time we demonstrate in global 3D simulations the collection of dust in long-lived vortices induced by the VSI. Without a pressure bump and for Z~0.01 and tau~0.01 we find that such vortices reach d/g density ratios slightly below unity in the discs mid-plane, while for Z>0.05 long-lived vortices are largely absent. In presence of a pressure bump, for Z~0.01 & tau~0.01 a dusty vortex forms reaching d/g ratios of a few times unity, such that the SI is expected to develop, before it eventually shears out into a turbulent dust ring. For Z~0.03 this occurs for tau~0.005, with a weaker, more short-lived vortex, while for larger tau only a turbulent dust ring forms. For Z>0.03 we find that the dust ring becomes increasingly axisymmetric for increasing tau and d/g ratios reach ~1 for tau>0.005. Furthermore, the disc's vertical mass flow profile is strongly affected by dust for Z>0.03, such that gas is transported inward near the mid-plane and outward at larger heights, i.e. the reversed situation compared to simulations with zero or small amounts of dust. Viscous $\alpha$-values drop moderately as 0.001-0.0001 for increasing Z=0-0.05. Our results suggest that the VSI can play an active role in planetesimal formation through the formation of vortices for plausible values of Z and tau. Also it may provide a natural explanation for the presence/absence of asymmetries of observed dust rings in PPDs, depending on the value of Z.

References in corpus (31)

• Protoplanetary Disk Structures in Ophiuchus
• Global simulations of protoplanetary disks with ohmic resistivity and ambipolar diffusion
• How to form planetesimals from mm-sized chondrules and chondrule aggregates
• Hall-effect Controlled Gas Dynamics in Protoplanetary Disks: II. Full 3D Simulations toward the Outer Disk
• Global Simulations of the Inner Regions of Protoplanetary Disks with Comprehensive Disk Microphysics
• Convective Overstability in radially stratified accretion disks under thermal relaxation
• Dust sedimentation and self-sustained Kelvin-Helmholtz turbulence in protoplanetary disk mid-planes. I. Radially symmetric simulations
• Vertical shear instability in accretion disc models with radiation transport
• Dust Trapping by Vortices in Transitional Disks: Evidence for Non-ideal MHD Effects in Protoplanetary Disks
• On the Stability of Elliptical Vortices in Accretion Discs
• Radiation Hydrodynamical Turbulence In Protoplanetary Disks: Numerical Models and Observational Constraints
• On the origin of horseshoes in transitional discs
• Effects of dust feedback on vortices in protoplanetary disks
• Convective overstability in accretion disks: 3D linear analysis and nonlinear saturation
• Baroclinic Vorticity Production in Protoplanetary Disks; Part II: Vortex Growth and Longevity
• Particle dynamics in discs with turbulence generated by the vertical shear instability
• Streaming Instability for Particle-Size Distributions
• Gas and dust dynamics in starlight-heated protoplanetary disks
• On the vertical-shear instability in astrophysical discs
• Vertical Shearing Instabilities in Radially Shearing Disks: The Dustiest Layers of the Protoplanetary Nebula
• A thermodynamic view of dusty protoplanetary disks
• Dust settling against hydrodynamic turbulence in protoplanetary discs
• Anisotropic hydrodynamic turbulence in accretion disks
• Effect of dust radial drift on viscous evolution of gaseous disk
• High Resolution Parameter Study of the Vertical Shear Instability
• Three-Dimensional Simulations of Kelvin-Helmholtz Instability in Settled Dust Layers in Protoplanetary Disks
• Long-Lived Dust Asymmetries at Dead Zone Edges in Protoplanetary Disks
• Stratified and vertically-shearing streaming instabilities in protoplanetary disks
• Streaming instability of multiple particle species II -- Numerical convergence with increasing particle number
• High Resolution Parameter Study of the Vertical Shear Instability II: Dependence on temperature gradient and cooling time
• On the local stability of vortices in differentially rotating discs

Cited by in corpus (8)

• The coexistence of the streaming instability and the vertical shear instability in protoplanetary disks: Planetesimal formation thresholds explored in two-dimensional global models
• Turbulent Dust-trapping Rings as Efficient Sites for Planetesimal Formation
• The saturation of the VSI in protoplanetary disks via parametric instability
• Instabilities in dusty non-isothermal proto-planetary discs
• Distinguishing Magnetized Disc Winds from Turbulent Viscosity through Substructure Morphology in Planet-forming Discs
• Formation of the First Planetesimals via the Streaming Instability in Globally Turbulent Protoplanetary Disks?
• Nonlinear Outcome of Coagulation Instability in Protoplanetary Disks II: Dust Ring Formation Mediated by Backreaction and Fragmentation
• A Large Double-ring Disk around the Taurus M Dwarf J04124068+2438157