The French Authority for Nuclear Safety and Radiation Protection (ASNR) oversees civil nuclear activities in France on behalf of the French State. It also carries out research, expert assessments, training, and public information in the fields of nuclear safety and radiation protection.
To assess the safety of nuclear facilities, relevance of radiation protection measures or remanence of radionuclides in environment, an important step is to determine the sources for airborne particulate contamination in normal operation and for different accident or post-accident scenarios. To this end, ASNR has been conducting experimental and numerical research on particle resuspension by turbulent airflow. Such phenomenon is also studied for other applications such as contamination and cleaning of solar panels and embedded systems, atmospheric pollution, ventilation ducts, among others. Significant progress was made in modelling particle resuspension considering the role of particle-surface, particle-flow and particle-particle interactions by using a Monte Carlo approach. Such advanced modeling was developed in the Granular Materials Laboratory (GML) belonging to the University of San Luis and to the CONICET, Argentina.

During a previous internship, we collaboratively developed a rebuilt version of one of the simulation codes in Python and verified its performance by comparing the results with those obtained from the original C++ version. The new code also includes several improvements and is capable of simulating the resuspension of both spherical particles and non-spherical particles formed by two joined spheres.
The GML has long experience implementing Monte Carlo algorithms for particle resuspension under diverse conditions, such as monodisperse and polydisperse particle size distributions, different models of particle–surface adhesion according to particle shape (spherical or irregular), particle materials, and a range of aerodynamic conditions. All codes, along with their associated subroutines, have been written in C++.
Building upon the development already carried out during the previous internship, the aim of the present work is to extend the rebuilt Python-based version of the code to include irregular particles of arbitrary shape. This will require implementing a second block in the code to handle particle and surface properties, aerodynamic conditions, model initialization, time loop configuration, and other related aspects.
In addition, the development of a user-friendly interface is planned to facilitate operational calculations under different aerodynamic resuspension scenarios and to make the complete code openly available to the scientific community. The programming should ensure that the code remains flexible and adaptable to evolving user needs over time.
The first step will consist of understanding the functionality of each code block already implemented in Python for the cases of spherical particles and doublets. This stage also includes the design of a user-friendly interface to assist potential users in exploring and defining key technical parameters. Verification of the results obtained with the existing Python code will also be performed.
The second step will focus on extending the code by adding the new block for irregular particles. This will involve defining shape parameters, modifying aerodynamic forces accordingly, and selecting appropriate adhesion models. Validation of this new block will be required to ensure reproducibility and consistency with the results obtained from the original C++ version.
Finally, the third step will be to extend the user interface to include irregular particles as an additional option for potential users.

Master 2 : Algorithm design and optimization, Monte Carlo and numerical methods, programming Python, computer science, applied mathematics.

La diversité est une des composantes de la politique RSE, RH et Qualité de Vie au Travail à l’ASNR.

Par conséquent, nous accordons la même considération à toutes les candidatures, sans discrimination, pour inclure tous les talents.

Quelles que soient les différences, nous souhaitons attirer, intégrer et fidéliser nos candidats et nos collaborateurs au sein d’un environnement de travail inclusif.

L'ASNR conduit une politique active depuis de nombreuses années en faveur de l'égalité des chances au travail et l'emploi des personnes handicapées. Si vous êtes en situation de handicap, n'hésitez pas à nous faire part de vos éventuels besoins spécifiques afin que nous puissions les prendre en compte.