Code Validation Engineer - Thermal Hydraulics
Blykalla AB · Oskarshamn · Tills vidare · Deadline 2026-11-18
Blykalla is recruiting a **Code Validation Engineer - Thermal Hydraulics** to join its Nuclear Engineering & Safety team, based at its offices in Stockholm, Oskarshamn, or the ARTS facility in Simpevarp. The position focuses on validating thermal-hydraulics system codes used in the design and safety analysis of lead-cooled fast reactors. Key responsibilities include coordinating, specifying, and analyzing experiments conducted at the ARTS test facility, contributing to code validation programs and methodologies, and serving as a technical lead for engineers and technicians working across experimental setups and simulation tools. For candidates based in Stockholm, **frequent monthly travel to ARTS** is expected. Candidates must hold a **master's degree in physics, engineering, or a related field**, paired with hands-on experience in designing, commissioning, and conducting thermal-hydraulic experiments, including data analysis and instrumentation. Applicants need a solid understanding of thermal hydraulics physics, experience building validation envelopes for system codes such as TRACE, RELAP, APROS, BISON, or CFD tools, and professional fluency in English. Helpful assets include experience with liquid metal applications, safety analysis of PWR, BWR, or advanced reactors, nuclear licensing or regulatory interactions, and proficiency in Swedish.
What we do at Blykalla
Blykalla is a global leader in advanced nuclear technology, commercialising the next generation of clean, reliable energy through its lead-cooled reactor, the SEALER. By combining decades of specialised research with world-class partners, Blykalla is building the backbone of the global AI and industrial economy. For more information, visit https://www.blykalla.com.
What you’ll get to do
We're seeking a Senior Thermal-Hydraulics Code Validation Engineer to join our Nuclear Engineering & Safety team, working from Stockholm or Oskarshamn. In this role, you will work on experiments with the aim of validating thermal-hydraulics system codes for use in the design and safety analysis of our lead-cooled fast reactors.
More specifically, you will
- Coordinate, specify and analyze experiments to be run in our ARTS (Advanced Reactor Testing Site) facility in Oskarshamn.
- Act as a technical lead for engineers and technicians working on both the experiments and the simulation codes.
- Contribute to our validation program for thermal hydraulics system codes and associated methodologies.
- Stay current with advances in thermal hydraulics, computational methods, and regulatory requirements.
Who you’ll get to work with
The thermal-hydraulics validation engineer sits in the Nuclear Engineering & Safety team within Blykalla, and reports to the manager of Nuclear Engineering & Safety. We are a diverse team that is passionate about our work and our company. You can choose to work from any of our offices in Stockholm, Oskarshamn or ARTS (at Simpevarp). In case of work from the Stockholm office, frequent (monthly) travel to the ARTS site is expected.
Who you are
You will be part of a highly skilled team with a can-do attitude. We value personal chemistry and strive to create a workplace where you enjoy coming to. There are however a few things that we think will help for you to succeed in this role, these are:
- Master's degree in physics, engineering or a related field
- Hands-on experience in designing, commissioning, and performing thermal-hydraulic experiments, including instrumentation and data analysis
- Familiarity with building validation envelopes for system codes used in nuclear safety analysis such as BISON (BWR), TRACE, RELAP, APROS or similar as well as for CFD tools
- Solid understanding of the physics and phenomena involved in thermal hydraulics simulations
- A structured way of working, together with excellent problem-solving and technical writing skills
- Fluency in English, spoken and written
Meritorious skills:
- Working experience in safety analysis of PWR, BWR or advanced reactors
- Working experience from liquid metal applications
- Experience in supporting nuclear licensing activities or in regulatory interaction
- Fluency in Swedish, spoken and written
If you are not sure that you are 100% qualified, but are up to the challenge, we encourage you to apply.
Location
This position is for our office in Stockholm, Oskarshamn or ARTS (Simpevarp)
So, what do you think?
Don't miss the chance to be at the forefront of revolutionizing nuclear power. Join our team as Senior Thermal-Hydraulics Code Validation Engineer and help shape the energy landscape of tomorrow. Apply today with your resume and a cover letter highlighting your relevant experience and achievements.
We are proud to foster an inclusive workplace free from discrimination. We strongly believe that diversity of experience, perspectives, and background will lead to a better environment for our employees and a better product. This is something we value deeply, and we encourage everyone to be a part of changing the way the world thinks about power supply!
Reference & Background Checks
As part of our recruitment process, we conduct background checks on all candidates. We may also conduct reference checks to gain a well-rounded understanding of your professional experience, performance, and ways of working. This includes both references provided by you and, where relevant, conversations with other professional contacts who have worked closely with you. We strive to be transparent about our reference-checking process and handle all personal data in accordance with applicable data protection regulations. Any additional references will be sought with professional judgment and only when considered relevant to the role.
Salary Range: SEK 57 000 - 95 000 / month, depending on experience and qualifications.
We offer competitive compensation aligned with our internal salary framework and growth potential in the role.
We do not accept applications via email.
We are not open to external help from recruitment agencies.
Note on AI Use: Blykalla may use AI technology to assist with certain administrative aspects of the hiring process, such as note-taking, interview documentation, and reporting. However, every resume and application is reviewed directly by our recruiting team. AI tools are used solely for operational support and do not influence candidate evaluation or hiring decisions.