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Wenshu Zhou

Publications and source records attributed to Wenshu Zhou.

6 recordsLinked to original sources

Normalized solutions to a class of Kirchhoff type equations with a logarithmic perturbation

This paper is devoted to the study of normalized solutions to the Kirchhoff type equation with a logarithmic perturbation\[-\left(a+b\int_{\mathbb{R}^3}|\nabla u|^2 \,\mathrm{d}x \right) Δu=λu+|u|^{p-2}u+u\log u^2,\quad x \in\mathbb{R}^3, \]under the normalized constraint $\int_{\mathbb{R}^3} u^2 \,\mathrm{d}x = c^2$, where $a,b>0$, $2 0$ is a constant, and $λ\in\mathbb{R}$ emerges as a Lagrange multiplier which is not a priori known. A unified variational framework is developed based on Orlicz spaces together with the Pohozaev constraint method and refined fiber map analysis. For $2<p<\frac{14}{3}$ or $p=\frac{14}{3}$ with small mass, the energy functional is bounded from below and admits a positive radial ground state minimizer. For $\frac{14}{3}<p<6$, where the energy functional is unbounded from below, we establish the existence of two normalized solutions for small mass: a ground state $u_c^+$ obtained via local minimization, and a second solution $u_c^-$ obtained via minimization on the negative component of the Pohozaev manifold. For the Sobolev critical case $p=6$, we construct a ground state solution and, under a technical condition on the parameters, a second solution by introducing a proper auxiliary functional and precise energy estimates with Aubin-Talenti bubbles. Asymptotically as $c\to0^+$, the $L^{2}$ norm of the gradient of ground state solution vanishes for $2<p\le6$. Surprisingly, for $\frac{14}{3}<p<6$, the $L^{2}$ norm of the gradient of the second solution diverges to infinity as $c\to 0^+$, while for $p=6$ it concentrates around the Aubin-Talenti bubble with energy converging to the energy level of the corresponding critical Kirchhoff equation.

math.AP↗

Vanishing Shear Viscosity Limit and Boundary Layer Study on the Planar MHD system

We consider an initial boundary problem for the planar MHD system under the general condition on the heat conductivity $κ$ that may depend on both the density $ρ$ and the temperature $θ$ satisfying $κ(ρ,θ)\geqκ_1 θ^{q}$ for some constants $κ_1>0$ and $q>0.$ Firstly, the global existence of strong solution for large initial data is obtained, and then the limit of the vanishing shear viscosity is justified. In addition, the $L^2$ convergence rate is obtained together with the estimation on the thickness of the boundary layer.

math.AP↗

Vanishing shear viscosity and boundary layers for plane magnetohydrodynamics flows

In this paper, we consider an initial-boundary problem for plane magnetohydrodynamics flows under the general condition on the heat conductivity $κ$ that may depend on both the density $ρ$ and the temperature $θ$ and satisfies $$ κ(ρ,θ)\geqκ_1(1+θ^{q}) \quad \hbox{\rm with constants}~ κ_1>0 ~\hbox{\rm and}~ q>0. $$ We prove the global existence of strong solutions for large initial data and justify the passage to the limit as the shear viscosity $μ$ goes to zero. Furthermore, the value $μ^α$ with any $0<α<1/2$ is established for the boundary layer thickness.

math.AP↗

Global Solvability and Vanishing Shear Viscosity Limit of Planar Magnetohydrodynamic Equations with Large Initial Data

By observing a new relation between the magnetic pressure and the hydrodynamic pressure, global existence of classical solution to the full perfect MHD equations with large data is established, in particular including the case when all the viscosity, heat conductivity and diffusivity coefficients are constant. This can be viewed as an analog of the classical work by Kazhikhov-Shelukhin for the Navier-Stokes equations to the MHD equations. In addition, the vanishing shear viscosity limit is proved.

math.AP↗