Thermal-Hydraulics Engineer
Transmutex
Geneva, Switzerland
Posted on Jul 7, 2025
Summary
Transmutex is seeking a skilled and highly motivated Thermal-Hydraulics engineer to drive the design development of our transmutation reactor. Join us if you have a passion for systems behavior and drive to advance cutting-edge nuclear designs.
About us
We are a Geneva-based start-up founded in 2019. We aim at reinventing nuclear energy by using an accelerator-driven system (ADS) to optimize the transmutation of long-lived nuclear waste. The innovative combination of particle accelerators and fuel, based on existing long-lived radioactive waste, will let us develop energy process that will be intrinsically safe, will reduce the stockpile of long-lived waste, is resistant to proliferation, and will be cost competitive.
Job description
We are seeking an adaptable and skilled thermal-hydraulics engineer, preferably with a nuclear engineering background to contribute to the design and development of thelead-cooled fast reactor. This role will involve performing system thermal-hydraulics analysis. The work will support design optimization and safety analysis of the subcritical reactor lead cooling system.
Key Responsibilities
- Perform system thermal-hydraulic analyses for normal operations and accidental conditions in the frame of the reactor safety analysis
- Perform core sub-channel analyses
- Perform detailed computational fluid dynamics (CFD)analysis for key reactor components
- Contribute and perform multi-physics calculations coupling neutronics, thermal-hydraulics and thermo-mechanical simulations
- Develop, maintain, and validate the thermal-hydraulic methodologies and modelling codes
- Collaborate with cross-functional teams for integrated reactor performance evaluations
- Contribute to internal reports and documentation for licensing efforts
Ideal candidate profile:
- Secondary university degree in Thermal Hydraulics Engineering, or a related field (Master’s or Ph.D. preferred)
- 3-5 years of experience in core and plant thermal-hydraulic analysis
- Good foundation in benchmarked system codes such as RELAP5, TRACE.
- Ability to work collaboratively in multicultural and multidisciplinary teams.
- Willingness to continuously learn and adapt to project needs.
- Proficiency in English
Additionally, it will be an advantage if you have:
- Knowledge and understanding of RELAP5-based thermal-hydraulic code structure, numerical methods, and correlations as well as their applicability in lead-based reactors.
- Prior experience with CFD using ANSYS-Fluent
- Proficiency in Fortran and Python languages
- Clear and demonstrated understanding of reactor systems and their technical specifications
- Experienced with coupled multi-physics calculations
- Proficiency in French, German or Italian
Starting date: as soon as possible
We offer competitive compensation package and social security, accident/disability insurance and pension plans; one day per week from home, as well as five weeks paid vacation.