Informations générales
Entité de rattachement
Le CEA est un acteur majeur de la recherche, au service des citoyens, de l'économie et de l'Etat.
Il apporte des solutions concrètes à leurs besoins dans quatre domaines principaux : transition énergétique, transition numérique, technologies pour la médecine du futur, défense et sécurité sur un socle de recherche fondamentale. Le CEA s'engage depuis plus de 75 ans au service de la souveraineté scientifique, technologique et industrielle de la France et de l'Europe pour un présent et un avenir mieux maîtrisés et plus sûrs.
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Les 20 000 collaboratrices et collaborateurs du CEA partagent trois valeurs fondamentales :
• La conscience des responsabilités
• La coopération
• La curiosité
Référence
2023-27005
Description de l'unité
SERMA is the reactor physics and applied mathematics division at CEA, whose main R&D activities concern code development, validation and application for the numerical simulation of nuclear systems, in the domain of radiation shielding, reactor physics and depletion, criticality-safety and nuclear instrumentation.
Situated within SERMA, the LTSD laboratory (Stochastic Transport and nuclear Data Lab) is in particular devoted to the development of the current generation (TRIPOLI-4) and next generation (TRIPOLI-5) Monte Carlo code for particle transport.
Description du poste
Domaine
Neutronique et physique des réacteurs
Contrat
Post-doctorat
Intitulé de l'offre
Large-scale depletion calculations with Monte Carlo neutron transport code H/F
Sujet de stage
One of the main goals of modern reactor physics is to perform accurate and
detailed multi-physics simulations of the behaviour of a nuclear reactor core.
Multi-physics calculations in nominal conditions imply a coupling between a
transport equation solver for the neutron and precursor populations, thermal
and thermal-hydraulics solvers, and a depletion solver. Such calculations still
represent a steep challenge from many points of view. Monte Carlo simulations
are the golden standard for neutron transport simulations, due to their exact
treatment of the energy variable in the Boltzmann equation. In 2018, CEA
performed a preliminary demonstration of Monte Carlo burnup calculation on a
full-scale PWR reactor core, without thermal-hydraulic feedback, using the
Monte Carlo neutron transport mini-app PATMOS and the depletion code MENDEL.
Later, in 2022, we performed a multi-physics simulation of a full PWR using
PATMOS and the THEDI thermal-hydraulics solver.
Durée du contrat (en mois)
12
Description de l'offre
The next step towards high-fidelity full-scale core calculations is to
integrate neutron burnup calculations with thermal-hydraulic feedback.
Achieving this result is the main goal of this post-doctoral position. The
proposed work is divided into two parts. First, the candidate will revisit and
extend the existing neutronics/depletion and neutronics/thermal-hydraulics
couplings in order to perform a fully-coupled
neutronics/thermal-hydraulics/depletion multi-physics calculation. The C3PO
(Collaborative Code Coupling Platform) code coupling platform will be used to
this effect. The target use case for the feasibility demonstration will be a
full-scale PWR reactor core with a number of depleted materials of the order of
several millions. Second, a study will be performed to evaluate the behavior,
performance, and stability of the coupled simulation. The emphasis will be
placed on the consequences of using a Monte Carlo solver for neutronics, which
enables high-fidelity simulations but by nature carries uncertainties and
statistical fluctuations on the estimated physical observables. Performance and
scalability tests will also be perfomed on the size of the reactor core, the
number of available CPU cores, and the number of depleted regions.
The work plan is the following:
- Study the bibliography of the state-of-the-art code-coupling schemes and
tools in neutronics, thermal-hydraulics and depletion physics;
- Acquire hands-on knowledge of the PATMOS code and existing PATMOS/MENDEL et
PATMOS/THEDI multi-physics couplings. Contribute to the verification and
analysis of these couplings;
- Develop a neutronics/thermal-hydraulics/depletion coupling using the C3PO
tool. Demonstrate the coupling on a set of full-scale PWR reactor core
simulations;
- Analyze the behavior of the proposed coupling schemes, study their
performance and scalability, with a focus on the impact of the Monte Carlo
neutronics solver on the results.
The candidate will be based in Saclay, in the Paris region, and will integrate
into the development team of TRIPOLI-5. TRIPOLI-5 is a next-generation Monte
Carlo particle transport code, developed at CEA and IRSN scientists since 2022.
The proposed duration of the initial contract is 12 months.
Moyens / Méthodes / Logiciels
Monte Carlo, TRIPOLI-5, depletion solver, THEDI, theral-hydraulics, multi-physics
Profil du candidat
PhD in nuclear engineering or computer science
Localisation du poste
Site
Saclay
Localisation du poste
France, Ile-de-France, Essonne (91)
Ville
Gif-sur-Yvette
Critères candidat
Diplôme préparé
Bac+8 - Doctor of philosophy (PhD)
Formation recommandée
Nuclear engineering / computer science / numerical simulation
Demandeur
Disponibilité du poste
02/10/2023