166 research outputs found
Finite element simulation of textile materials at the fiber scale
A general approach to simulate the mechanical behavior of textile materials
by taking into account all their constitutive elementary fibers and contacts
between them is presented in this paper. A finite element code, based on an
implicit solver, is develop to model samples of woven fabrics as assemblies of
beams submitted to large displacements and developing contactfriction
interactions between themselves. Special attention is paid to the detection and
modeling of the numerous contacts occurring in this kind of structures. Robust
models and efficient algorithms allow to consider samples made of few hundreds
of fibers. The unknown initial configuration of the woven fabric is obtained by
simulation according to the chosen weaving pattern, providing useful
informations on fibers trajectories and tows crosssections shapes. Various
loading cases can then be applied to the textile sample, in presence of an
elastic matrix, so as to identify its mechanical behavior under different
solicitations. Results of simulations performed on coated fabric samples are
given to illustrate the approach
A finite element approach of the behaviour of woven materials at microscopic scale
A finite element simulation of the mechanical behaviour of woven textile
materials at the scale of individual fibers is proposed in this paper. The aim
of the simulation is to understand and identify phenomena involved at different
scales in such materials. The approach considers small patches of woven textile
materials as collections of fibers. Fibers are modelled by 3D beam elements,
and contact-friction interactions are considered between them. An original
method for the detection of contacts, and the use of efficient algorithms to
solve the nonlinearities of the problem, allow to handle patches made of few
hundreds of fibers. The computation of the unknown initial configuration of the
woven structure is carried out by simulating the weaving process. Various
loading cases can then be applied to the studied patches to identify their
mechanical characteristics. To approach the mesoscopic behaviour of yarns, 3D
strains are calculated at the scale of yarns, as post-processing. These strains
display strong inhomogeinities, which raises the question of using continuous
models at the scale of yarns
Une approche pour la simulation numĂ©rique des milieux enchevĂȘtrĂ©s et des structures tissĂ©es
Une approche du comportement mĂ©canique de milieux enchevĂȘtrĂ©s par la simulation Ă©lĂ©ments finis Ă l'Ă©chelle des fibres est proposĂ©e dans ce papier. Cette approche, qui repose principalement sur une mĂ©thode originale de dĂ©tection et de prise en compte des contacts entre fibres, permet de traiter des Ă©chantillons de quelques centaines de fibres. Des applications Ă des mileux enchevĂȘtrĂ©s gĂ©nĂ©ralisĂ©s et Ă des matĂ©riaux composites textiles sont prĂ©sentĂ©es comme rĂ©sultats
Simulation of Frictional Contact Interactions Between Warp Yarns and Heddles Within Jacquard Harness for 3d Weaving
The relative motions between warp yarns and heddles within the Jacquard harness used for 3D weaving induce frictional interactions between these elements which may generate both damage in the yarns and weaving errors. To identify the interaction phenomena taking place within such harnesses, a finite element model, based on an implicit solution scheme [1], is proposed. In this model, all elements involved in the harness (cords, heddles, warp yarns) are represented using finite strain beam elements, and frictional contact elements are automatically created to account for frictional contact interactions. Motions defined by the Jacquard card for the shedding are prescribed as boundary conditions to the upper ends of the heddles. The resultant forces necessary to move the heddles are obtained as results of the simulation. Simulation results for an interlock fabric, with 28 warp yarns, will be presented, showing the forces evolution applied to the heddles over a few dozen consecutive sheddings
Simulation numĂ©rique du comportement de milieux fibreux enchevĂȘtrĂ©s
National audienceSee http://hal.archives-ouvertes.fr/docs/00/59/28/87/ANNEX/r_ML247501.pd
Numerical Simulation of the Mechanical Behavior of Fibrous Materials at Microscopic Scale
International audienc
Numerical simulation of the mechanical behaviour of woven and non-woven materials
International audienc
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