Damien André

The GranOO workbench, a new tool for developing discrete element simulations, and its application to tribological problems

This work was supported by the Conseil Regional d’Aquitaine and was conducted under the auspices of the Etude et Formation en Surfacage Optique (EFESO 2) project.

A Quantitative Discrete Element Model to Investigate Sub-Surface Damage due to Surface Polishing

This work is a continuation of a previous study that investigated sub-surface damage in silica glass due to surface polishing. In this previous study, discrete element models have shown qualitatively good agreement with experiments. The presented work propose a model allowing quantitative results by focusing on the continuous part of the problem. Special attemption was given to the discrete element model of silica glass considered as perfectly isotropic, elastic and brittle. To validate this approach, numerical results are compared to experimental data from literature.Copyright

Development of the GranOO Discrete Element Platform for Dynamic Problems: Application for Tribological Application

Discrete Model is based on the description of the physical state (velocity, position, temperature, magnetic moment, electric potential ..) of a large number of discrete elements that form the media to be studied. It is not basedon a continuous description of the media. Thus, it is particularly well adapted to describe media evolution driven by discontinuous phenomena like the description of multi fracturation followed by debris flow like wear study.Recently, the use of discrete model has been widened to face problem encountered with complex rheological behavior and/or multi-physical behavior. Multi-physical problems face complex mathematical formulation because of the mixing of different families of differential equations when continuous approach is chosen. With the discrete model, each particle has a physical state and state evolution is due to local physical particle interaction: it is often much simple to write. From the beginning of the years 2000, this method has been widely applied for the study of tribological problems. Wear has been investigated[1], thermo-mechanical behavior of a contact[2], subsurface damage due to surface polishing[4]… Recently, it has been shownhow quantitative results can be obtained with this method[4]. To help and promote research in this area, a platform GranOO has been developed under a C++ environment and is distributed under thefree GPL license. The goal of this platform is to offer to researchers, especially in the tribology domain, a numerical and easy to use environment to facilitate the access to Discrete Element simulations. The main aspect of this platform ispresented in the extended abstract and some applicationsgiven as examples. Details can be found on url www.granoo.org.Copyright