2 research outputs found
Potential Vorticity Evolution of a Protoplanetary Disk with An Embedded Protoplanet
We present two-dimensional inviscid hydrodynamic simulations of a
protoplanetary disk with an embedded planet, emphasizing the evolution of
potential vorticity (the ratio of vorticity to density) and its dependence on
numerical resolutions. By analyzing the structure of spiral shocks made by the
planet, we show that progressive changes of the potential vorticity caused by
spiral shocks ultimately lead to the excitation of a secondary instability. We
also demonstrate that very high numerical resolution is required to both follow
the potential vorticity changes and identify the location where the secondary
instability is first excited. Low-resolution results are shown to give the
wrong location. We establish the robustness of a secondary instability and its
impact on the torque onto the planet. After the saturation of the instability,
the disk shows large-scale non-axisymmetry, causing the torque on the planet to
oscillate with large amplitude. The impact of the oscillating torque on the
protoplanet's migration remains to be investigated.Comment: 17 pages total with 9 figures (Fig.4,5,9 are in .jpg), accepted to
Ap