Simulations of dust-trapping vortices in protoplanetary discs

¹ NORDITA, Blegdamsvej 17, 2100 Copenhagen, Denmark e-mail: [anja; brandenb]@nordita.dk
² Astronomical Obs., NBIfAFG, Copenhagen University, Juliane Maries Vej 30, 2100 Copenhagen, Denmark

Corresponding author: A. Johansen, ajohan@astro.ku.dk

Received: 30 September 2003
Accepted: 18 December 2003

Abstract

Local three-dimensional shearing box simulations of the compressible coupled dust-gas equations are used in the fluid approximation to study the evolution of different initial vortex configurations in a protoplanetary disc and their dust-trapping capabilities. The initial conditions for the gas are derived from an analytic solution to the compressible Euler equation and the continuity equation. The solution is valid if there is a vacuum outside the vortex. In the simulations the vortex is either embedded in a hot corona, or it is extended in a cylindrical fashion in the vertical direction. Both configurations are found to survive for at least one orbit and lead to accumulation of dust inside the vortex. This confirms earlier findings that dust accumulates in anticyclonic vortices, indicating that this is a viable mechanism for planetesimal formation.