Postdoc - Nuclear Fuel Performance and Fission Gas Modelling

# Postdoc - Nuclear Fuel Performance and Fission Gas Modelling

The prolonged storage of spent nuclear fuel, particularly high burn up, requires specific knowledge of chemical, structural, radiological and mechanical processes that occur within the fuel assemblies which may impact their stability during storage. In addition to this, reliably predicting the medium-longer term performance is essential for safe storage and associated licensing.

As part of the Ministry for Environment, Climate Action, Nature Conservation and Nuclear Safety (BMUKN) project “Atlas”, the [Institute of Fusion Energy and Nuclear Waste Management (IFN) / Nuclear Waste Management (IFN-2)](https://www.fz-juelich.de/en/ifn/ifn-2)is offering a Postdoc position for a motivated individual with a PhD and background in computational materials science to investigate the chemical and mechanical effects arising from delayed fission gas release in high burn-up spent nuclear fuel by applying SCIANTIX modelling and coupling this against fundamental and engineering-scale nuclear codes such as BISON and TRANSURANUS. The position will run for 3 years and is contingent upon project approval.

## Your Job

• Apply and develop state-of-the-art computational investigative methods, specifically utilizing the SCIANTIX code, to simulate the behavior of high burn-up spent nuclear fuel during extended interim storage
• Predictive Analysis: Model and evaluate physical-chemical phenomena—such as diffusion, resolution, and bubble evolution, to deliver enhanced predictions of fission gas release (FGR) and structural engineering performance in spent fuel
• Bridge the gap between theory and experiment by integrating microstructural and experimental data into computational models to validate predictive capabilities
• Assist in coupling mesoscale fission gas behavior models with macroscopic fuel performance codes such as BISON and TRANSURANUS to assess the long-term integrity of storage systems
• Actively collaborate and exchange benchmarks with the "Atlas" project partners, including participating in collaborative research exchanges
• Support and mentor PhD and Masters level students in implementing modelling codes and analysis
• Analyze, document, and present data at international conferences and publish findings in high-impact, peer-reviewed scientific journals

## Your Profile

• Master's degree with subsequent PhD degree in Nuclear Engineering, Computational Materials Science, Physics, Chemistry, or a closely related discipline
• Proven experience in mesoscale or engineering-scale modeling of nuclear fuel materials. Familiarity with physics-based rate theory, mechanistic modeling, or fuel performance codes such as SCIANTIX particularly but also TRANSURANUS or BISON is highly desirable
• Strong foundational knowledge in fission gas behavior (including diffusion, bubble nucleation, resolution, and microstructural evolution) and the mechanics of high burn-up spent nuclear fuel under extended interim storage conditions
• Solid scientific programming and data analysis skills (e.g., Python, C++ or Fortran) for script development, code execution, and parsing complex data sets
• Ability to independently design, execute, and troubleshoot your research output while aligning results with the overarching goals of the Atlas project
• Assist in the co-supervision and mentoring of PhD candidates, master’s students, or technical staff working within the research group whilst performing an active leadership role in the Atlas project
• Excellent English communication and scientific writing skills (at least B2 level according to the [CEFR](https://go.fzj.de/languagerequirements)), with a demonstrated track record of publishing in peer-reviewed journals

## Our Benefits for You

We work on highly topical, socially relevant issues and offer you the opportunity to actively shape change! You can expect a wide range of opportunities:

• **Research Environment:** Working within the state-of-the-art nuclear laboratories of Forschungszentrum Juelich, [Institute of Fusion Energy and Nuclear Waste Management (IFN) / Nuclear Waste Management (IFN-2)](https://www.fz-juelich.de/en/ifn/ifn-2)
• **Research infrastructure:** Access to state-of-the-art computational infrastructure
• **Mentoring & Expertise:** Mentoring and training by global experts in nuclear fuel materials chemistry and condensed matter physics
• **Knowledge & further training:** Support for further career growth, with the flexibility to develop your own independent scientific ideas within the project's scope
• **International networking:** Confirmed funded opportunities to attend international conferences and training events
• **Vacation:** You will receive 30 days of vacation plus additional days off (e.g. between Christmas and New Year's)
• **Health & well-being:** Your health is important to us. You can look forward to a comprehensive occupational health management program with a wide range of offerings - e.g., a beach volleyball court, running groups, yoga classes, and much more. In addition, our company medical service and an experienced social counseling team are available to assist you on site
• **Support for international employees:** Our International Advisory Service makes it easier for international employees to get started
• **Career Center:** You will receive [explicit support with regard to your career development opportunities](https://go.fzj.de/careercenter)
• **Successful start:** It is important to us that you quickly settle into the team and are given structured training for your tasks. We also support you from the very beginning and make your start easier with our [Welcome Days and Welcome Guide](https://go.fzj.de/welcome)
• **Fair remuneration:** Depending on your existing qualifications and the tasks assigned to you, you will be classified in pay grade EG 13 of the TVöD-Bund (Collective Agreement for the Public Service). All information on the TVöD-Bund collective agreement can be found on the[BMI website](https://go.fzj.de/bmi.tvoed). The monthly salaries in euros can be found on page 69 ff. of the PDF download
• **Additional benefits:** Benefit from attractive additional services such as a company pension scheme with employer contribution. In addition to the basic salary, there is an additional year-end bonus under the collective pay agreement amounting to 75% of a monthly salary, as well as capital-forming benefits
• **Fixed-term:** 3 Year position contingent upon project approval

In addition to exciting tasks and a collegial working environment, we offer you much more: [https://go.fzj.de/benefits](https://go.fzj.de/benefits)

We welcome applications from people with diverse backgrounds, e.g. in terms of age, gender, disability, sexual orientation / identity, and social, ethnic and religious origin. A diverse and inclusive working environment with equal opportunities in which everyone can realize their potential is important to us.

The following links provide further information on diversity and equal opportunities: [https://go.fzj.de/equality](https://go.fzj.de/equality) and on specific support options: [https://go.fzj.de/womens-job-journey](https://go.fzj.de/womens-job-journey)

• *Place of Employment:**Jülich
• *Start Date:** As soon as possible
• *Working Hours:** 39 Hours / Week
• *Salary:** EG 13 TVöD-Bund
• *Application Deadline: The position will be published until it is successfully filled.**

[Application Process](https://go.fzj.de/ApplicationInformation) [FAQ](https://go.fzj.de/FAQ_eng) [Contact form](mailto:?subject=Query%20about%202026T-0499%20Postdoc%20-%20Nuclear%20Fuel%20Performance%20and%20Fission%20Gas%20Modelling)

[Career portal](https://go.fzj.de/Careers) [Forschungszentrum Jülich GmbH](https://www.fz-juelich.de/en) [Legal Notice](https://cs-media.b-ite.com/forschungszentrum-juelich/impressum-recruiting-en.pdf)