Work

A Quantitative Hydrodynamic Limit for the Vlasov-Fokker-Planck/Navier-Stokes System in the Fine Particle Regime

Year: 2026

Type: preprint

Abstract: We justify the hydrodynamic limit of the Vlasov-Fokker-Planck equation coupled with the incompressible Navier--Stokes equation in the fine regime with a quantitative convergence rate. In this regime, the limiting dynamics is described by the inhomogeneous incompressible Navier-Stokes system for the fluid-particle mixture. In contrast with the existing relative entropy approaches, the present work extends to a pointwise convergence of the hydrodynamic limits with an explicit rate on any given time interval [0,T]. The proof is based on a Macro-Micro decomposition around the moving local Maxwellian, together with an $\varepsilon$-weighted energy-dissipation structure adapted to the fine particle relaxation scales. Furthermore, we remove the classical small background restriction inherent in high-order energy methods, allowing the limiting profile to be possibly large. This is accomplished by exploiting a hidden Kelvin-Voigt type damped wave equation structure within the macroscopic velocity error system, yielding the critical extra dissipation required to close the uniform estimates.

Source: arXiv (Cornell University)

DOI: 10.48550/arxiv.2610.21119

Authors: Fang, Zhendong, Li, Jian, Qi, Kunlun, Wen, Huanyao

Institutions: Guangzhou University, South China University of Technology, Michigan State University

Language: English

Topic: Gas Dynamics and Kinetic Theory

Subfield: Applied Mathematics

Field: Mathematics

Domain: Physical Sciences

Open Access status: green

Funders: Michigan State University, National Natural Science Foundation of China, College of Engineering, Michigan State University

Award: G5056213642

OpenAlex ID: W7222476405

Cites: 1

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Related to: 10