Section: Software

Simulation of fibrous materials

Participants : Florence Bertails-Descoubes, Gilles Daviet.

The goal of the MECHE ADT, which started in September 2009 and was completed in fall 2011, was to develop a software for simulating the dynamics of assemblies of thin rods (such as hair), subject to contact and friction. This software combines a panel of well-accepted models for rods (ranging from reduced coordinates to maximal coordinates models, and including models recently developed by some members of the group) with classical as well as innovative schemes for solving the problem of frictional contact (incorporating the most recent results of the group, as well as the new contact solver we published in [21] ). The aim of this software is twofold: first, we were able to compare and analyze the performance of nonsmooth schemes for the frictional contact problem, in terms of realism (capture of dry friction, typically), robustness, and computational efficiency. This study was conducted onto the different rod models that are available in the software. Second, we believe such a software will help us understand the behavior of a fibrous material (such as hair) through virtual experiments, thanks to which we hope to identify and understand some important emergent phenomena. A careful validation study against experiments started to be conducted in 2011 in collaboration with physicists from L'Oréal. Once this discrete elements model will be fully validated, our ultimate goal would be to build a continuous macroscopic model for the hair medium relying on nonsmooth laws.

An associate engineer, Gilles Daviet, has been hired in September 2009 to work full-time on the MECHE project. His contract was extended until October the 31st, funded by the L'Oréal collaboration project.