Gaussian kinetic representations of rarefied nonequilibrium flows

Ehsan Roohi

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arXiv · 2607.05753

Gaussian kinetic representations of rarefied nonequilibrium flows

Ehsan Roohi

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Abstract

Compact representations of rarefied flows must preserve kinetic observables, not only smooth macroscopic fields. We introduce Gaussian kinetic representations for discrete velocity method (DVM)-Shakhov solutions of normal shocks and a lid-driven cavity. A positive log-density phase-space model reconstructs shock velocity distribution functions (VDFs) and their moments, while a moment-field model compresses wall-bounded cavity structure. Log-density training recovers heat flux, stress, and third- and fourth-order shock moments without explicit moment supervision; the cavity representation gives a compact continuous wall-transport map.

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Ehsan Roohi. 2026-07-07. Gaussian kinetic representations of rarefied nonequilibrium flows. https://arxiv.org/abs/2607.05753

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