{ "id": "2210.16600", "version": "v1", "published": "2022-10-29T13:45:42.000Z", "updated": "2022-10-29T13:45:42.000Z", "title": "Stability and large-time behavior on 3D incompressible MHD equations with partial dissipation near a background magnetic field", "authors": [ "Hongxia Lin", "Jiahong Wu", "Yi Zhu" ], "comment": "46 pages", "categories": [ "math.AP" ], "abstract": "Physical experiments and numerical simulations have observed a remarkable stabilizing phenomenon: a background magnetic field stabilizes and damps electrically conducting fluids. This paper intends to establish this phenomenon as a mathematically rigorous fact on a magnetohydrodynamic (MHD) system with anisotropic dissipation in $\\mathbb R^3$. The velocity equation in this system is the 3D Navier-Stokes equation with dissipation only in the $x_1$-direction while the magnetic field obeys the induction equation with magnetic diffusion in two horizontal directions. We establish that any perturbation near the background magnetic field $(0,1,0)$ is globally stable in the Sobolev setting $H^3(\\mathbb R^3)$. In addition, explicit decay rates in $H^2(\\mathbb R^3)$ are also obtained. When there is no presence of the magnetic field, the 3D anisotropic Navier-Stokes equation in $\\mathbb R^3$ is not well understood and the small data global well-posedness remains an intriguing open problem. This paper reveals the mechanism of how the magnetic field generates enhanced dissipation and helps stabilize the fluid.", "revisions": [ { "version": "v1", "updated": "2022-10-29T13:45:42.000Z" } ], "analyses": { "subjects": [ "35B35" ], "keywords": [ "background magnetic field", "3d incompressible mhd equations", "partial dissipation", "large-time behavior", "field generates enhanced dissipation" ], "note": { "typesetting": "TeX", "pages": 46, "language": "en", "license": "arXiv", "status": "editable" } } }