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Effective energy integral functionals for thin films with three dimensional bending moment in the Orlicz-Sobolev space setting

Włodzimierz Laskowski, Hong Thai Nguyen (2016)

Discussiones Mathematicae, Differential Inclusions, Control and Optimization

In this paper we consider an elastic thin film ω ⊂ ℝ² with the bending moment depending also on the third thickness variable. The effective energy functional defined on the Orlicz-Sobolev space over ω is described by Γ-convergence and 3D-2D dimension reduction techniques. Then we prove the existence of minimizers of the film energy functional. These results are proved in the case when the energy density function has the growth prescribed by an Orlicz convex function M. Here M is assumed to be non-power-growth-type...

Effects of In-plane Elastic Stress and Normal External Stress on Viscoelastic Thin Film Stability

F. Closa, F. Ziebert, E. Raphaël (2012)

Mathematical Modelling of Natural Phenomena

Motivated by recent experiments on the electro-hydrodynamic instability of spin-cast polymer films, we study the undulation instability of a thin viscoelastic polymer film under in-plane stress and in the presence of either a close by contactor or an electric field, both inducing a normal stress on the film surface. We find that the in-plane stress affects both the typical timescale of the instability and the unstable wavelengths. The film stability...

Efficient application of e-invariants in finite element method for an elastodynamic equation

Martin Balazovjech, Ladislav Halada (2013)

Kybernetika

We introduce a new efficient way of computation of partial differential equations using a hybrid method composed from FEM in space and FDM in time domain. The overall computational scheme is explicit in time. The key idea of the suggested way is based on a transformation of standard basis functions into new basis functions. The results of this matrix transformation are e-invariants (effective invariants) with such suitable properties which save the number of arithmetical operations needed for a...

Efficient inexact Newton-like methods with application to problems of the deformation theory of plasticity

Radim Blaheta, Roman Kohut (1993)

Applications of Mathematics

Newton-like methods are considered with inexact correction computed by some inner iterative method. Composite iterative methods of this type are applied to the solution of nonlinear systems arising from the solution of nonlinear elliptic boundary value problems. Two main quastions are studied in this paper: the convergence of the inexact Newton-like methods and the efficient control of accuracy in computation of the inexact correction. Numerical experiments show the efficiency of the suggested composite...

Equi-integrability results for 3D-2D dimension reduction problems

Marian Bocea, Irene Fonseca (2002)

ESAIM: Control, Optimisation and Calculus of Variations

3D-2D asymptotic analysis for thin structures rests on the mastery of scaled gradients α u ε | 1 ε 3 u ε bounded in L p ( Ω ; 9 ) , 1 < p < + . Here it is shown that, up to a subsequence, u ε may be decomposed as w ε + z ε , where z ε carries all the concentration effects, i.e. α w ε | 1 ε 3 w ε p is equi-integrable, and w ε captures the oscillatory behavior, i.e. z ε 0 in measure. In addition, if { u ε } is a recovering sequence then z ε = z ε ( x α ) nearby Ω .

Equi-integrability results for 3D-2D dimension reduction problems

Marian Bocea, Irene Fonseca (2010)

ESAIM: Control, Optimisation and Calculus of Variations

3D-2D asymptotic analysis for thin structures rests on the mastery of scaled gradients α u ε | 1 ε 3 u ε bounded in L p ( Ω ; 9 ) , 1 < p < + . Here it is shown that, up to a subsequence, u ε may be decomposed as w ε + z ε , where z ε carries all the concentration effects, i.e. α w ε | 1 ε 3 w ε p is equi-integrable, and w ε captures the oscillatory behavior, i.e. z ε 0 in measure. In addition, if { u ε } is a recovering sequence then z ε = z ε ( x α ) nearby Ω .

Etude asymptotique de la jonction d'un massif tridimensionnel et d'une tige élancée en flexion.

B. Mampassi (1994)

Revista Matemática de la Universidad Complutense de Madrid

We are very interested with asymptotic problems for the system of elasticity involving small parameters in the description of the domain where the solutions is searched. The corresponding asymptotic expansions have different forms in the various between them. More precisely, our work is concerned with a precise description of the deformation and the stress fields at the junction of an elastic three-dimensional body and a cylinder. The corresponding small parameter is the diameter of the cylinder....

Eulerian formulation and level set models for incompressible fluid-structure interaction

Georges-Henri Cottet, Emmanuel Maitre, Thomas Milcent (2008)

ESAIM: Mathematical Modelling and Numerical Analysis

This paper is devoted to Eulerian models for incompressible fluid-structure systems. These models are primarily derived for computational purposes as they allow to simulate in a rather straightforward way complex 3D systems. We first analyze the level set model of immersed membranes proposed in [Cottet and Maitre, Math. Models Methods Appl. Sci.16 (2006) 415–438]. We in particular show that this model can be interpreted as a generalization of so-called Korteweg fluids. We then extend this model...

Existence and decay in non linear viscoelasticity

Jaime E. Muñoz Rivera, Félix P. Quispe Gómez (2003)

Bollettino dell'Unione Matematica Italiana

In this work we study the existence, uniqueness and decay of solutions to a class of viscoelastic equations in a separable Hilbert space H given by u t t + M ( [ u ] ) A u - 0 t g ( t - τ ) N ( [ u ] ) A u d τ = 0 , in L 2 ( 0 , T ; H ) u ( 0 ) = u 0 , u t ( 0 ) = u 1 where by u t we are denoting [ u ( t ) ] = ( u ( t ) , u t ( t ) , ( A u ( t ) , u t ( t ) ) , A 1 2 u ( t ) 2 , A 1 2 u t ( t ) 2 , A u ( t ) 2 5 A : D ⁢...

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