Nuclear Safety Analyst Severe Accident


Job description

SCK•CEN is working on the design of MYRRHA, a multi-purpose irradiation installation.  MYRRHA is part of the research into and development of a reactor technology that allows the transmutation of long-lived and highly radiotoxic isotopes from highly radioactive waste of the current generation of commercial nuclear production plants to shorter-lived and less radiotoxic isotopes. MYRRHA is a flexible fast spectrum research reactor that is driven by an Accelerator Driven System (ADS). It consists of a 600 MeV proton linear accelerator, a spallation target and a multiplication core with fissile material cooled with liquid lead-bismuth.
SCK•CEN aims to obtain a permit for the construction of MYRRHA in 2028. In order to obtain this permit, a thorough safety demonstration of the installation must be provided. This function is part of the safety analysis of the MYRRHA reactor and, more specifically, the safety analysis of accidents in which the shell of the fissile material fails because the cooling of the core is lost.
Working environment
The expert group "Nuclear Systems Physics" (or NSP for short) is responsible for the safety analysis of the MYRRHA installation and is also largely responsible for the safety design of this installation
NSP is made up of Engineers and Physicists who draw up models that allow the real behaviour of the installation to be reliably predicted in circumstances involving accidents. The studies using these models make it possible to demonstrate that the installation is capable of dealing with postulated accidents in a safe manner or must indicate which modifications to the design of the installation are necessary to cope with these accidents.  Accidents in which the normal cooling of the core is lost (Severe Accidents) have the potential to have a major impact on the design of the installation. They may require additional systems to bring the highly degraded situation under control.
At present, the NSP team consists of about 12 people who have thermohydraulic and/or reactor physics expertise. This team will be considerably strengthened in order to obtain a building permit by 2028.
Job description
As a "Nuclear Safety Analyst Severe Accident", you are jointly responsible for determining the strategy on how Severe Accidents can be detected in MYRRHA without giving rise to serious discharges to the environment.  In order to determine this strategy and to demonstrate its effectiveness, models must be developed that are capable of realistically or conservatively predicting the behaviour of the installation in highly degraded Severe Accident conditions.
At present, the analysis of Severe Accidents is primarily carried out using models in SIMMER (a coupled thermohydraulic/neutronic code) and using simplified conservative analytical calculations.
The development of reliable models to study these severe accidents requires an extremely in-depth understanding of thermohydraulics and reactor physics.
In many cases, it concerns models and solutions that are innovative and scientific in nature and the results of which can be published in the relevant professional literature.

Required qualifications

• Master's degree in engineering sciences, preferably with a specialisation in thermohydraulics and/or reactor physics;
• Experience in solving complex thermohydraulic and neutron-physical problems.
• Experience with CFD packages (OpenFOAM and/or ANSYSFluent) would be a plus
• A PhD in a thermohydraulic subject would be a plus.
• Good knowledge of English.
• Knowledge of Dutch and/or French would be an advantage.
• A thorough and careful approach to work in terms of quality.


Should you have any questions, please contact

Deben Frederik
+32 (0)14 33 25 72