2025/05/29 by Niklas Knobel, Knobel, Niklas · 2 citations
Mathematics · Engineering · #Navier-Stokes equation solutions #Stability and Controllability of Differential Equations #Advanced Mathematical Physics Problems
paper · pdf · doi:10.48550/arxiv.2505.23391
We study the Sobolev stability thresholds of 2d dissipative fluid equations around Couette flow on the domain \mathbb T× \mathbb R. We prove a bound for general nonlinear interactions, which, for several fluid equations, reduces the proof of nonlinear stability to a linear stability analysis. We apply this approach to the examples of Navier-Stokes, Boussinesq and magnetohydrodynamic equations around Couette flow. This improves the Sobolev stability threshold for the Boussinesq equations around Couette flow and large affine temperature to 1/3 and for the MHD equations around Couette flow and constant magnetic field to 1/3+.