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A Numerical Approach of the sentinel method for distributed parameter systems

Aboubakari Traore, Benjamin Mampassi, Bisso Saley (2007)

Open Mathematics

In this paper we consider the problem of detecting pollution in some non linear parabolic systems using the sentinel method. For this purpose we develop and analyze a new approach to the discretization which pays careful attention to the stability of the solution. To illustrate convergence properties we give some numerical results that present good properties and show new ways for building discrete sentinels.

A parabolic quasilinear problem for linear growth functionals.

Fuensanta Andreu, Vincent Caselles, José María Mazón (2002)

Revista Matemática Iberoamericana

We prove existence and uniqueness of solutions for the Dirichlet problem for quasilinear parabolic equations in divergent form for which the energy functional has linear growth.

A parabolic system in a weighted Sobolev space

Adam Kubica, Wojciech M. Zajączkowski (2007)

Applicationes Mathematicae

We examine the regularity of solutions of a certain parabolic system in the weighted Sobolev space W 2 , μ 2 , 1 , where the weight is of the form r μ , r is the distance from a distinguished axis and μ ∈ (0,1).

A phase-field model of grain boundary motion

Akio Ito, Nobuyuki Kenmochi, Noriaki Yamazaki (2008)

Applications of Mathematics

We consider a phase-field model of grain structure evolution, which appears in materials sciences. In this paper we study the grain boundary motion model of Kobayashi-Warren-Carter type, which contains a singular diffusivity. The main objective of this paper is to show the existence of solutions in a generalized sense. Moreover, we show the uniqueness of solutions for the model in one-dimensional space.

A posteriori error control for the Allen–Cahn problem : circumventing Gronwall’s inequality

Daniel Kessler, Ricardo H. Nochetto, Alfred Schmidt (2004)

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

Phase-field models, the simplest of which is Allen–Cahn’s problem, are characterized by a small parameter ε that dictates the interface thickness. These models naturally call for mesh adaptation techniques, which rely on a posteriori error control. However, their error analysis usually deals with the underlying non-monotone nonlinearity via a Gronwall argument which leads to an exponential dependence on ε - 2 . Using an energy argument combined with a topological continuation argument and a spectral...

A posteriori error control for the Allen–Cahn problem: circumventing Gronwall's inequality

Daniel Kessler, Ricardo H. Nochetto, Alfred Schmidt (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

Phase-field models, the simplest of which is Allen–Cahn's problem, are characterized by a small parameter ε that dictates the interface thickness. These models naturally call for mesh adaptation techniques, which rely on a posteriori error control. However, their error analysis usually deals with the underlying non-monotone nonlinearity via a Gronwall argument which leads to an exponential dependence on ε-2. Using an energy argument combined with a topological continuation argument and...

A posteriori estimates for the Cahn–Hilliard equation with obstacle free energy

Ľubomír Baňas, Robert Nürnberg (2009)

ESAIM: Mathematical Modelling and Numerical Analysis

We derive a posteriori estimates for a discretization in space of the standard Cahn–Hilliard equation with a double obstacle free energy. The derived estimates are robust and efficient, and in practice are combined with a heuristic time step adaptation. We present numerical experiments in two and three space dimensions and compare our method with an existing heuristic spatial mesh adaptation algorithm.

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