General information
Organisation
The French Alternative Energies and Atomic Energy Commission (CEA) is a key player in research, development and innovation in four main areas :
• defence and security,
• nuclear energy (fission and fusion),
• technological research for industry,
• fundamental research in the physical sciences and life sciences.
Drawing on its widely acknowledged expertise, and thanks to its 16000 technicians, engineers, researchers and staff, the CEA actively participates in collaborative projects with a large number of academic and industrial partners.
The CEA is established in ten centers spread throughout France
Reference
SL-DES-24-0140
Thesis topic details
Category
Engineering science
Thesis topics
Modeling the nonlinear dynamics of CEA wear testing machines: prediction of vibratory regimes with impact and friction, and bifurcations.
Contract
Thèse
Job description
In the industrial context of pressurized water reactors (PWR) within the French nuclear power plant fleet, the internal components of PWRs susceptible to wear are subject to special monitoring. Faced with these challenges, EDF and CEA aim to enhance the understanding and prediction of wear phenomena, not only to optimize maintenance operations and improve component design but also to optimize research and development efforts while ensuring the reliability of the obtained results.
Among the technical and scientific objectives set within the framework of their collaboration since 2014, the development and improvement of wear testing equipment and associated digital twins is of particular importance, with the modeling of wear testing machines considered a priority.
The state of the art in the field of nonlinear dynamics modeling of mechanical systems with clearances has led recent research at CEA towards the modeling of vibratory wear testing machines, particularly the MUSE* tribometer and its two electromagnetic actuators. Encouraging initial results have been obtained through the modeling of a single actuator. Identifying the different vibratory regimes involving impact and friction and the bifurcations of this machine is of crucial importance for understanding the testing apparatus. This knowledge will enable more precise specifications for wear tests and better control of the necessary contact conditions for studying the phenomenon.
The thesis work will involve modeling the nonlinear dynamics of both types of vibratory wear testing machines at CEA. The numerical developments to be carried out in Python and using the finite element code Cast3M (http://www-cast3m.cea.fr/) will complement the existing computational tools and will be proposed to determine a comprehensive map of vibratory regimes with impact and friction, as well as bifurcations. The results of the simulations will be compared to those from experiments conducted within the scope of this thesis to validate and improve the proposed computational models.
Graduates of top engineering schools or holders of a Master's degree (M2), the candidate should have skills in structural and materials mechanics, and in numerical simulation.
At the end of the thesis, the student's experience can be put to good use in research positions in industry (nuclear, automotive, rail, aeronautics, medical, etc.), and in the academic network.
An M2 internship on the same subject is offered prior to the thesis. Applying for this internship is not a requirement for the thesis, but it could be an asset for the student.
* : Moyen d’essais d’USure en environnement REP of the CEA-DES/ISAS/DM2S/SEMT Paris-Saclay RESEDA’s platform.
University / doctoral school
Mécanique, Energétique, Génie civil, Acoustique (MEGA)
INSA Lyon
Thesis topic location
Site
Saclay
Requester
Position start date
01/10/2024
Person to be contacted by the applicant
FAYARD Jean-Luc jean-luc.fayard@cea.fr
CEA
DES/DM2S/SEMT/DYN
Laboratoire d'études de DYnamique,
CEA Paris-Saclay
(+33) 01 69 08 84 15
Tutor / Responsible thesis director
BAGUET Sébastien Sebastien.Baguet@insa-lyon.fr
INSA-Lyon
LAMCOS
INSA Lyon - LaMCoS
Bât. Sophie Germain
Campus LyonTech-La Doua
27bis avenue Jean Capelle
F69621 Villeurbanne Cedex
En savoir plus