On Navier-Stokes equations arising from the rotation of an obstacle in a fluid
Tahar Zamène Boulmezaoud, Nabil Kerdid, Amel Kourta
TL;DR
This work analyzes stationary Navier–Stokes-type equations in ${\mathbb R}^3$ exterior to a rotating rigid body, incorporating rotation through terms like $\hat{\omega}\times u$ and $(\hat{\omega}\times x)\cdot\nabla u$. By employing weighted Sobolev spaces, the authors characterize decay at infinity and establish an existence/uniqueness theory for weak solutions under small forcing, together with detailed regularity and asymptotic decay results. The proof combines a linear theory for the rotated-Stokes-type operator $-\Delta v + \mathscr{R}v + \nabla r$ with a fixed-point argument to handle the nonlinear convection $u\cdot\nabla u$, yielding quantitative decay rates such as $|x|^{2-\varepsilon}$ in $L^p(S^2)$ norms for the velocity and $|x|^{3-\varepsilon}$ for the pressure. The results extend prior linear/augmented analyses and provide a robust framework for understanding far-field behavior of rotating-fluid interactions with potential extensions via Mozzi–Chasles transformations.
Abstract
We consider the modified Navier-Stokes equations in R3 describing the motion of a fluid in the presence of a rotating rigid body. Weighted Sobolev spaces are used to describe the behavior of solutions at large distances. Under suitable assumptions, w e prove the existence and regularity of solutions satisfying appropriate conditions at infinity.
