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Homogenization of the Maxwell equations: Case I. Linear theory

Niklas Wellander (2001)

Applications of Mathematics

The Maxwell equations in a heterogeneous medium are studied. Nguetseng’s method of two-scale convergence is applied to homogenize and prove corrector results for the Maxwell equations with inhomogeneous initial conditions. Compactness results, of two-scale type, needed for the homogenization of the Maxwell equations are proved.

Homogenization of the Maxwell Equations: Case II. Nonlinear conductivity

Niklas Wellander (2002)

Applications of Mathematics

The Maxwell equations with uniformly monotone nonlinear electric conductivity in a heterogeneous medium, which may be non-periodic, are homogenized by two-scale convergence. We introduce a new set of function spaces appropriate for the nonlinear Maxwell system. New compactness results, of two-scale type, are proved for these function spaces. We prove existence of a unique solution for the heterogeneous system as well as for the homogenized system. We also prove that the solutions of the heterogeneous...

Il criterio dell'energia e Vequazione di Maxwell-Cattaneo nella termodinamica dei sistemi elettromagnetici non lineari

Ettore Laserra, Giovanni Matarazzo (1985)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

We study the evolution law of the canonical energy of an electromagnetic material, immersed in an environment that is thermally and electromagnetically passive, at constant temperature. We use as constitutive equation for the heat flux a Maxwell-Cattaneo like equation.

Improved successive constraint method based a posteriori error estimate for reduced basis approximation of 2D Maxwell's problem

Yanlai Chen, Jan S. Hesthaven, Yvon Maday, Jerónimo Rodríguez (2009)

ESAIM: Mathematical Modelling and Numerical Analysis


In a posteriori error analysis of reduced basis approximations to affinely parametrized partial differential equations, the construction of lower bounds for the coercivity and inf-sup stability constants is essential. In [Huynh et al., C. R. Acad. Sci. Paris Ser. I Math.345 (2007) 473–478], the authors presented an efficient method, compatible with an off-line/on-line strategy, where the on-line computation is reduced to minimizing a linear functional under a few linear constraints. These constraints...

Integral Equations VIA Saddle Point Problem for 2D Electromagnetic Problems

Nathalie Bartoli, Francis Collino (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

A new system of integral equations for the exterior 2D time harmonic scattering problem is investigated. This system was first proposed by B. Després in [11]. Two new derivations of this system are given: one from elementary manipulations of classical equations, the other based on a minimization of a quadratic functional. Numerical issues are addressed to investigate the potential of the method.

L2-stability of the upwind first order finite volume scheme for the Maxwell equations in two and three dimensions on arbitrary unstructured meshes

Serge Piperno (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

We investigate sufficient and possibly necessary conditions for the L2 stability of the upwind first order finite volume scheme for Maxwell equations, with metallic and absorbing boundary conditions. We yield a very general sufficient condition, valid for any finite volume partition in two and three space dimensions. We show this condition is necessary for a class of regular meshes in two space dimensions. However, numerical tests show it is not necessary in three space dimensions even on regular...

Mathematical and numerical studies of non linear ferromagnetic materials

Patrick Joly, Olivier Vacus (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

In this paper we are interested in the numerical modeling of absorbing ferromagnetic materials obeying the non-linear Landau-Lifchitz-Gilbert law with respect to the propagation and scattering of electromagnetic waves. In this work we consider the 1D problem. We first show that the corresponding Cauchy problem has a unique global solution. We then derive a numerical scheme based on an appropriate modification of Yee's scheme, that we show to preserve some important properties of the continuous...

Maxwell’s equations revisited – mental imagery and mathematical symbols

Matthias Geyer, Jan Hausmann, Konrad Kitzing, Madlyn Senkyr, Stefan Siegmund (2023)

Archivum Mathematicum

Using Maxwell’s mental imagery of a tube of fluid motion of an imaginary fluid, we derive his equations curl 𝐄 = - 𝐁 t , curl 𝐇 = 𝐃 t + 𝐣 , div 𝐃 = ϱ , div 𝐁 = 0 , which together with the constituting relations 𝐃 = ε 0 𝐄 , 𝐁 = μ 0 𝐇 , form what we call today Maxwell’s equations. Main tools are the divergence, curl and gradient integration theorems and a version of Poincare’s lemma formulated in vector calculus notation. Remarks on the history of the development of electrodynamic theory, quotations and references to original and secondary literature complement...

Currently displaying 61 – 80 of 157