research

Abstract

This paper presents a design methodology based on a combination of isogeometric analysis (IGA),

level set and point wise density mapping techniques for topology optimization of piezoelectric /

flexoelectric materials. The fourth order partial differential equations (PDEs) of flexoelectricity,

which require at least C 1 continuous approximations, are discretized using Non-Uniform Rational

B-spline (NURBS). The point wise density mapping technique with consistent derivatives is

Soft elastic layers with top and bottom surfaces adhered to rigid bodies are abundant in biological organisms and engineering applications. As the rigid bodies are pulled apart, the stressed layer can exhibit various modes of mechanical instabilities. In cases where the layer’s thickness is much smaller than its length and width, the dominant modes that have been studied are the cavitation, interfacial and fingering instabilities. Here we report a new mode of instability which emerges if the thickness of the constrained elastic layer is comparable to or smaller than its width.

The size- and shape-dependency of the chemo-mechanical behavior of spherical and ellipsoidal nanoparticles in Li-ion battery electrodes are investigated by a stress-assisted diffusion model and 3D finite element simulations. The model features surface tension, a direct coupling between diffusion and elasticity, concentration-dependent diffusivity, and a Butler-Volmer relation for the description of electrochemical reactions that is modified to account for mechanical effects.

Abstract

A finite element software computes the stresses and/or strains sets values at each dynamic iteration step. These values can be plotted on a stress-space giving several failure envelopes. For an isotropic or an homogeneous mixture the Von Mises criterion represents an ideal envelope which may not coincide with the available envelopes but the stresses values can be checked with the material strength.

The Mechanical Laboratory of Sousse (LMS) of the National School of Engineers of Sousse intends to organize annual scientific workshop on one of the four research themes identified by the laboratory teams. This first Workshop is proposed by the LMS team: “Fatigue of Materials and Structures”. The proposed theme is ” Mechanical performance of materials: From experiments to predictive approaches”.

The Mechanical Laboratory of Sousse (LMS) of the National School of Engineers of Sousse intends to organize annual scientific workshop on one of the four research themes identified by the laboratory teams. This first Workshop is proposed by the LMS team: “Fatigue of Materials and Structures”. The proposed theme is ” Mechanical performance of materials: From experiments to predictive approaches”.

https://arxiv.org/abs/1610.01694

http://legato-team.eu/isogeometric-finite-element-analysis-of-time-harm…

New preprint.

Stéphane Bordas