PhD Thesis in Molten Salt Reactor Physics (M/F)

Job Description

Thesis Subject

Development of an Advanced Numerical Model for
Depletion Calculations in Molten-Salt Reactors and Application to the Preliminary Design of
Experiments for Reducing Uncertainties

Description of the subject
Molten Salt Reactors (MSR) present a very interesting potential in terms of safety and flexibility. Such
reactor is based on a liquid salt circulating between the core and the heat exchangers and playing the
role of both the fuel to produce heat and the coolant to evacuate the heat produced. Due to its inherent
features, and its flexible applications (power generation (from small modular reactors up to high power,
burning actinides that may not be used as fuel in present Pressurized Water Reactors, etc.), since some
times, there is renewed interest in these reactors in France, Europe, and over the world. In the past twenty
years, the MSFR team of LSPC (Laboratoire de Physique Subatomique et de Cosmologie) drives studies
of such reactors for all these applications and especially the reference MSFR version, breeder reactor in
the Thorium fuel cycle and based on a fluoride fuel salt.
As part of research on molten-salt reactors, new research topics are emerging related to material
evolution (Bateman equation) under constraints, while taking into account uncertainties in nuclear data
that affect neutron transport (Boltzmann equation).
The objective of this PhD thesis is to establish a link between algorithms dedicated to neutronic
evolution and the correlated sampling (CS) method. Indeed, evolution is based on a matrix that
associates each isotope with its variation resulting from neutron irradiation, its natural decay rates, and
any source or sink terms. The advantage of the CS method is that it allows one to estimate, within a
single transport calculation, the impact of a change in effective cross-sections on all relevant quantities,
such as the reaction rates in the evolution matrix.
To this end, the PhD thesis is divided into two parts: first, to study innovative algorithms for performing
evolution calculations by revisiting previous work using new tools; and second, to enable the
propagation of uncertainties in nuclear databases regarding final inventories. In light of these
developments, an additional issue concerns the preliminary experimental design aimed at reducing
uncertainties through Bayesian assimilation in databases.
This work will draw on past developments in reactor physics modeling in the MSFR team of LPSC,
with potential contributions to national or European projects on molten salt reactors in which members
of the MSFR team are involved.

The candidate must have a Master degree in reactor physics or in nuclear physics.
• Have a good knowledge about reactor physics (neutronics, thermalhydraulics, safety…)
• Be able to work in a team and in various collaborations
• Be able to develop a simulation/calculation tool, especially with the Python and C++ languages
• Master a large production of data
• Master the French and English languages, both written and spoken

Your Work Environment

The Grenoble Laboratory of Subatomic Physics and Cosmology (LPSC) (http://lpsc.in2p3.fr) is a joint research unit involving the CNRS-IN2P3, the University of Grenoble Alpes (UGA) and Grenoble INP, with an average staff of around 230 people.
The successful candidate will be assigned to the MSFR team and will report to the team leader

Compensation and benefits

Compensation

2300 € gross monthly

Annual leave and RTT

44 jours

Remote Working practice and compensation

Pratique et indemnisation du TT

Transport

Prise en charge à 75% du coût et forfait mobilité durable jusqu’à 300€

About the offer

About the CNRS

The CNRS is a major player in fundamental research on a global scale. The CNRS is the only French organization active in all scientific fields. Its unique position as a multi-specialist allows it to bring together different disciplines to address the most important challenges of the contemporary world, in connection with the actors of change.

CNRS

The research professions