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Navier-Stokes equations on unbounded domains with rough initial data

Peer Christian Kunstmann (2010)

Czechoslovak Mathematical Journal

We consider the Navier-Stokes equations in unbounded domains Ω n of uniform C 1 , 1 -type. We construct mild solutions for initial values in certain extrapolation spaces associated to the Stokes operator on these domains. Here we rely on recent results due to Farwig, Kozono and Sohr, the fact that the Stokes operator has a bounded H -calculus on such domains, and use a general form of Kato’s method. We also obtain information on the corresponding pressure term.

Neumann problems associated to nonhomogeneous differential operators in Orlicz–Sobolev spaces

Mihai Mihăilescu, Vicenţiu Rădulescu (2008)

Annales de l’institut Fourier

We study a nonlinear Neumann boundary value problem associated to a nonhomogeneous differential operator. Taking into account the competition between the nonlinearity and the bifurcation parameter, we establish sufficient conditions for the existence of nontrivial solutions in a related Orlicz–Sobolev space.

New regularity results for a generic model equation in exterior 3D domains

Stanislav Kračmar, Patrick Penel (2005)

Banach Center Publications

We consider a generic scalar model for the Oseen equations in an exterior three-dimensional domain. We assume the case of a non-constant coefficient function. Using a variational approach we prove new regularity properties of a weak solution whose existence and uniqueness in anisotropically weighted Sobolev spaces were proved in [10]. Because we use some facts and technical tools proved in the above mentioned paper, we give also a brief review of its results and methods.

New results on the Burgers and the linear heat equations in unbounded domains.

J.I. Díaz, S. González (2005)

RACSAM

We consider the Burgers equation and prove a property which seems to have been unobserved until now: there is no limitation on the growth of the nonnegative initial datum u0(x) at infinity when the problem is formulated on unbounded intervals, as, e.g. (0 +∞), and the solution is unique without prescribing its behaviour at infinity. We also consider the associate stationary problem. Finally, some applications to the linear heat equation with boundary conditions of Robin type are also given.

New unilateral problems in stratigraphy

Stanislav N. Antontsev, Gérard Gagneux, Robert Luce, Guy Vallet (2006)

ESAIM: Mathematical Modelling and Numerical Analysis

This work deals with the study of some stratigraphic models for the formation of geological basins under a maximal erosion rate constrain. It leads to introduce differential inclusions of degenerated hyperbolic-parabolic type 0 t u - d i v { H ( t u + E ) u } , where H is the maximal monotonous graph of the Heaviside function and E is a given non-negative function. Firstly, we present the new and realistic models and an original mathematical formulation, taking into account the weather-limited rate constraint in the conservation...

New wall laws for the unsteady incompressible Navier-Stokes equations on rough domains

Gabriel R. Barrenechea, Patrick Le Tallec, Frédéric Valentin (2002)

ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique

Different effective boundary conditions or wall laws for unsteady incompressible Navier-Stokes equations over rough domains are derived in the laminar setting. First and second order unsteady wall laws are proposed using two scale asymptotic expansion techniques. The roughness elements are supposed to be periodic and the influence of the rough boundary is incorporated through constitutive constants. These constants are obtained by solving steady Stokes problems and so they are calculated only once....

New Wall Laws for the Unsteady Incompressible Navier-Stokes Equations on Rough Domains

Gabriel R. Barrenechea, Patrick Le Tallec, Frédéric Valentin (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

Different effective boundary conditions or wall laws for unsteady incompressible Navier-Stokes equations over rough domains are derived in the laminar setting. First and second order unsteady wall laws are proposed using two scale asymptotic expansion techniques. The roughness elements are supposed to be periodic and the influence of the rough boundary is incorporated through constitutive constants. These constants are obtained by solving steady Stokes problems and so they are calculated only...

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