Including Dust Coagulation in Hydrodynamic Models of Protoplanetary Disks: Dust Evolution in the Vicinity of a Jupiter-mass Planet

TL;DR

This paper introduces a numerical model that couples hydrodynamic evolution with dust coagulation in protoplanetary disks containing a Jupiter-mass planet, revealing the importance of detailed dust growth modeling for accurate disk evolution predictions.

Contribution

It presents a novel coupled 2-D hydrodynamic and dust coagulation simulation framework, including multiple dust fluids and solving the Smoluchowski equation, advancing the modeling of dust evolution in disks.

Findings

Fragmentation in pressure bumps increases small grain density.

Full coagulation models differ from fixed-size approaches.

A simple method can approximate dust size in simulations.

Abstract

Dust growth is often neglected when building models of protoplanetary disks due to its complexity and computational expense. However, it does play a major role in shaping the evolution of protoplanetary dust and planet formation. In this paper, we present a numerical model coupling 2-D hydrodynamic evolution of a protoplanetary disk, including a Jupiter-mass planet, and dust coagulation. This is obtained by including multiple dust fluids in a single grid-based hydrodynamic simulation and solving the Smoluchowski equation for dust coagulation on top of solving for the hydrodynamic evolution. We find that fragmentation of dust aggregates trapped in a pressure bump outside of the planetary gap leads to an enhancement in density of small grains. We compare the results obtained from the full coagulation treatment to the commonly used, fixed dust size approach and to previously applied, less computationally intensive methods for including dust coagulation. We find that the full coagulation results cannot be reproduced using the fixed-size treatment, but some can be mimicked using a relatively simple method for estimating the characteristic dust size in every grid cell.