Code Validation Engineer - Thermal Hydraulics

Blykalla; Stockholms kommun; On-site; SEK 636,000 - 1,060,000; Full time

Job summary

Blykalla is seeking a Senior Thermal-Hydraulics Code Validation Engineer to join the Nuclear Engineering & Safety team, based in Stockholm, Oskarshamn, or ARTS. You will coordinate experiments at ARTS, lead engineers and technicians, and contribute to validation of system codes for safety analyses of lead-cooled reactors.

The role requires a Master’s degree, hands-on experimental experience, and strong technical writing. English fluency is essential; Swedish is a plus.

Qualifications

• Master's degree in physics, engineering or related field.
• Hands-on experience in designing, commissioning, and performing thermal-hydraulic experiments, including instrumentation and data analysis.
• Familiarity with validation envelopes for system codes (BISON, TRACE, RELAP, APROS) and CFD tools.
• Solid understanding of the physics and phenomena involved in thermal hydraulics simulations.
• A structured way of working with strong problem-solving and technical writing skills.
• Fluency in English, spoken and written.
• Meritorious: Swedish fluency, experience with PWR/BWR or advanced reactors, nuclear licensing exposure, and experience with liquid metal applications.

Responsibilities

• Coordinate, specify and analyze experiments at ARTS facility in Oskarshamn.
• Act as technical lead for engineers and technicians on experiments and simulation codes.
• Contribute to the validation program for thermal-hydraulics system codes and methodologies.
• Stay current with advances in thermal hydraulics, computational methods and regulatory requirements.

Skills

Thermal-hydraulics experiments

Instrumentation & data analysis

English fluency

Problem solving

Structured working method

Education

Master's degree in physics or engineering

Tools

CFD tools

Job description

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?

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 toexternal 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.