MULTIGRAIN: A smoothed particle hydrodynamics algorithm for multiple small dust grains and gas

TL;DR

MULTIGRAIN is a new explicit algorithm for simulating multiple dust grain populations in gas, improving accuracy by modeling backreaction effects and coupling dust phases in astrophysical environments.

Contribution

It introduces a novel, efficient, and explicit method for simulating multiple dust grain populations with backreaction effects in gas dynamics.

Findings

More accurate than single-phase models

Efficient, low-storage computational approach

Captures dust-gas interactions in astrophysical contexts

Abstract

We present a new algorithm, MULTIGRAIN, for modelling the dynamics of an entire population of small dust grains immersed in gas, typical of conditions that are found in molecular clouds and protoplanetary discs. The MULTIGRAIN method is more accurate than single-phase simulations because the gas experiences a backreaction from each dust phase and communicates this change to the other phases, thereby indirectly coupling the dust phases together. The MULTIGRAIN method is fast, explicit and low storage, requiring only an array of dust fractions and their derivatives defined for each resolution element.