POSTE : Numerical modelling of knitted fabric (PhD or Post-Doc)

Advisors

Thibaut Métivet (INRIA Rhône-Alpes, ELAN) thibaut.metivet@inria.fr

Florence Bertails-Descoubes (INRIA Rhône-Alpes, ELAN) florence.descoubes@inria.fr

Mélina Skouras (INRIA Rhône-Alpes, IMAGINE) melina.skouras@inria.fr

Hosting Laboratory

ELAN team (INRIA and LJK, Grenoble), https://team.inria.fr/elan/

Practical details

PhD thesis (3 years) or post-doctoral position (1 year renewable), salary as defined in Inria scales. Start in fall 2020.

http://elan.inrialpes.fr/people/bertails/SujetsThesePostDoc2020/sujetTricot.pdf

Context:

Although it is made of almost inextensible yarns, knitted fabric exhibits an extremely stretchable mechanical behaviour, a highly desirable property in meta-material engineering. Furthermore, knitted fabric makes is possible to design arbitrarily shaped objects, either in 2D or 3D, with a predictable mechanical response. For these reasons, knitted fabric has recently gained a renewed and growing interest from industry and various fields of science – from physics to computer graphics. In physics, Poincloux and colleagues [6] have recently studied experimentally the tensile response of a model knitted patch in order to characterise relevant ingredients explaining the macroscopic mechanical behavior of knitted yarns, and started to derive a reduced continuum model. In graphics, complex simulations of 3D knitted fabric have been set-up for more than a decade [4, 5, 2], relying on a discrete element strategy where yarns and contacts between yarns are explicitly modelled. Only recently, a numerically homogenised model has been presented [7], which simulates knitted fabric as a thin elastic shell with a modified constitutive law fitted from simulated data. Although impressive, all these simulations have however never been validated against experiments, and the particular role of friction has never been investigated.

Objectives:

The goal of the project is to develop numerical models for the study of knitted fabric. A first part of the PhD will be dedicated to the discrete element modelling of a model tricot, its validation against experiments, and the careful study of the role of friction. A second part will deal with the continuum modelling of the tricot using an analytical approach, which will be validated against the discrete element simulator. The project will involve collaborations with physicists to validate both models.

Keywords:

Numerical modelling, analysis and simulation, mechanics of thin elastic rods, dry frictional contact, plates and shells, numerical and theoretical homogenisation.