A rigorous model reduction for the anisotropic-scattering transport process

TL;DR

This paper introduces a mathematically rigorous reduced-order model that accurately captures anisotropic-scattering transport physics in highly scattered regimes, bridging microscopic particle mechanics and macroscopic fluid dynamics.

Contribution

It presents a novel, rigorous model reduction approach for anisotropic-scattering transport processes with arbitrary scattering order, validated by numerical experiments.

Findings

Model prediction aligns with numerical results

Reveals diffusion physics in optically thick regime

Provides a concise physical interpretation

Abstract

In this letter, we propose a reduced-order model to bridge the particle transport mechanics and the macroscopic fluid dynamics in the highly scattered regime. A rigorous mathematical derivation and a concise physical interpretation are presented for an anisotropic-scattering transport process with arbitrary order of scattering kernel. The prediction of the theoretical model perfectly agrees with the numerical experiments. A clear picture of the diffusion physics is revealed for the neutral particle transport in the asymptotic optically thick regime.