existence and uniqueness results for quasi-linear elliptic equations with nonlinear boundary conditions
-theory of the Navier-Stokes flow in the exterior of a moving or rotating obstacle.
-theory of the Navier-Stokes flow in the exterior of a moving or rotating obstacle
-approach to weak solutions of the Oseen flow around a rotating body
We consider the time-periodic Oseen flow around a rotating body in ℝ³. We prove a priori estimates in -spaces of weak solutions for the whole space problem under the assumption that the right-hand side has the divergence form. After a time-dependent change of coordinates the problem is reduced to a stationary Oseen equation with the additional term -(ω ∧ x)·∇u + ω ∧ u in the equation of momentum where ω denotes the angular velocity. We prove the existence of generalized weak solutions in -space...
L2 Decay for the Navier-Stokes Flow in Halfspaces.
Lagrangian approximations and weak solutions of the Navier-Stokes equations
The motion of a viscous incompressible fluid flow in bounded domains with a smooth boundary can be described by the nonlinear Navier-Stokes equations. This description corresponds to the so-called Eulerian approach. We develop a new approximation method for the Navier-Stokes equations in both the stationary and the non-stationary case by a suitable coupling of the Eulerian and the Lagrangian representation of the flow, where the latter is defined by the trajectories of the particles of the fluid....
Laminar Slip-Flow Through A Uniform Circular Pipe With Small Suction
Laminar slip-flow through a uniform circular pipe with small suction.
Large deviation principle and inviscid shell models.
Le problème du plus court chemin en hydrodynamique incompressible
L’élément -bulle/
Les théorèmes de Leray et de Fujita-Kato pour le système de Boussinesq partiellement visqueux
Dans cet article, on étudie le système de Boussinesq décrivant le phénomène de convection dans un fluide incompressible et visqueux. Ce système est composé des équations de Navier-Stokes incompressibles avec un terme de force verticale dont l’amplitude est transportée sans dissipationpar le flot du champ de vitesses. On montre que les résultats classiques pour le système de Navier-Stokes standard demeurent vrais pour le système de Boussinesq bien qu’il n’y ait pas d’amortissement sur le terme de...
Letter to the editor.
Limiting behavior for an iterated viscosity
Limiting Behavior for an Iterated Viscosity
The behavior of an ordinary differential equation for the low wave number velocity mode is analyzed. This equation was derived in [5] by an iterative process on the two-dimensional Navier-Stokes equations (NSE). It resembles the NSE in form, except that the kinematic viscosity is replaced by an iterated viscosity which is a partial sum, dependent on the low-mode velocity. The convergence of this sum as the number of iterations is taken to be arbitrarily large is explored. This leads to a limiting...
Linear flow in porous media with double periodicity.
Linear flow problems in 2D exterior domains for 2D incompressible fluid flows
The paper analyzes the issue of existence of solutions to linear problems in two dimensional exterior domains, linearizations of the Navier-Stokes equations. The systems are studied with a slip boundary condition. The main results prove the existence of distributional solutions for arbitrary data.
Linear instability implies nonlinear instability for various types of viscous boundary layers
Linearization and normal form of the Navier-Stokes equations with potential forces
Linear-quadratic optimal control for the Oseen equations with stabilized finite elements
For robust discretizations of the Navier-Stokes equations with small viscosity, standard Galerkin schemes have to be augmented by stabilization terms due to the indefinite convective terms and due to a possible lost of a discrete inf-sup condition. For optimal control problems for fluids such stabilization have in general an undesired effect in the sense that optimization and discretization do not commute. This is the case for the combination of streamline upwind Petrov-Galerkin (SUPG) and pressure...