报告人：许孝精
报告题目：On the Sobolev stability threshold for 3D Navier-Stokes equations with rotation near the Couette flow
报告时间：2025年9月20日9：30-10：30
报告方式：腾讯会议(268-972-170)
报告摘要：In this talk, we investigate the dynamic stability of periodic, plane Couette flow in the three-dimensional Navier-Stokes equations with rotation at high Reynolds number $\mathbf{Re}$. Our aim is to determine the stability threshold index on $\mathbf{Re}$: the maximum range of perturbations within which the solution remains stable. Initially, we examine the linear stability effects of a linearized perturbed system. Comparing our results with those obtained by Bedrossian, Germain, and Masmoudi [Ann. Math. 185(2): 541–608 (2017)], we observe that mixing effects (which correspond to enhanced dissipation and inviscid damping) arise from Couette flow while Coriolis force acts as a restoring force inducing a dispersion mechanism for inertial waves that cancels out lift-up effects occurred at zero frequency velocity. This dispersion mechanism exhibits favorable algebraic decay properties distinct from those observed in classical 3D Navier-Stokes equations. Consequently, we demonstrate that if initial data satisfies $\left\|u_{\mathrm{in}}\right\|_{H^{\sigma}}<\delta \mathbf{Re}^{-1}$ for any $\sigma>\frac{9}{2}$ and some $\delta=\delta(\sigma)>0$ depending only on $\sigma$, then the solution to the 3D Navier-Stokes equations with rotation is global in time without transitioning away from Couette flow. This is a joint work with Wenting Huang and Ying Sun.
报告人简介：许孝精，北京师范大学数学科学学院教授，博士生导师，数学建模教育中心执行主任。主要研究流体力学数学理论，给出了一系列Boussinesq方程的适定性理论。曾获“吉林省优秀博士学位论文”、北京市优秀教学成果奖、北师大励耘优秀青年教师奖一等奖、校优秀博士生学位指导教师、校优质课程特等奖等。主持了多项国家自然科学基金，发表学术论文60余篇，被引用970余次，大部分成果发表在J.Math.Pures Appl.（JMPA）, J. Funct. Anal.(JFA), SIAM J.Math. Anal.(SIAM), Nonlinearity, JDE等国际知名学术期刊，曾在法国、美国、加拿大、波兰和香港等地区进行学术访问10余次。
