On the initial-boundary value problem for the 2D partially dissipative Oldroyd-B model: global well-posedness and large time stability
Zhenrong Nong, Yinghui Wang, Huancheng Yao, Shihao Zhang
TL;DR
This work analyzes the 2D Oldroyd-B model with purely horizontal viscosity, proving global well-posedness for arbitrarily large initial data on domains $[0,1]\times\mathbb{R}$ and $[0,1]\times\mathcal{T}$, and establishing long-time stability in the periodic-strip setting for small data. The authors employ energy methods combined with anisotropic Sobolev inequalities and maximum-principle structure to control the stress-velocity coupling and to compensate for the lack of vertical dissipation. Key contributions include a hierarchical set of a priori estimates (from $L^{2}$ to $H^{2}$ and time-derivatives) that close the global existence argument, and, in the periodic case, uniform-in-time bounds and exponential decay to equilibrium for small perturbations. The results highlight how domain geometry and anisotropic regularization enhance dissipation in viscoelastic flows and provide rigorous long-time behavior for this partially dissipative system.
Abstract
This paper establishes the global well-posedness of solutions to the Oldroyd-B model with purely horizontal viscosity and arbitrarily large initial data in two-dimensional settings, including the full space $\mathbb{R}^2$, the partially periodic domain $\mathcal{T}\times\mathbb{R}$ and the fully periodic torus $\mathcal{T}^2$, where $\mathcal{T}$ represents the one-dimensional periodic torus. Our analysis relies on energy methods to derive key {\it a priori} estimates that capture the anisotropic regularization induced by horizontal viscosity. Furthermore, for the cases of spatial domains $\mathcal{T}\times\mathbb{R}$ and $\mathcal{T}^2$, we further investigate the long-time behavior of solutions with small initial data. The compactness along the horizontal direction plays a pivotal role in constructing uniform-in-time estimates, ultimately leading to exponential decay of solutions as $t\to\infty$. This decay mechanism reveals how geometric constraints enhance the dissipation in viscoelastic flows.
