On the Relation of Exact Hydrodynamics to the Chapman-Enskog Series
Mathematical Physics
2025-06-25 v1 Analysis of PDEs
math.MP
Abstract
We demonstrate that the Chapman-Enskog series is locally equivalent to the exact spectral closure defined on slow kinetic eigenmodes in the limit of vanishing Knudsen number. We further show that the Chapman-Enskog series diverges everywhere expect at the global equilibrium for an explicit example, while the exact spectrally closed hydrodynamics are defined globally for any Knudsen number.
Keywords
Cite
@article{arxiv.2506.17441,
title = {On the Relation of Exact Hydrodynamics to the Chapman-Enskog Series},
author = {Florian Kogelbauer and Ilya Karlin},
journal= {arXiv preprint arXiv:2506.17441},
year = {2025}
}