Relap5-3D Code Modernization Engineer

Idaho National Laboratory; Idaho Falls (ID); On-site; USD 79,000 - 195,000; Full time

Benefits offered by this job

Relocation package

401(k) with employer contribution

Job summary

Idaho National Laboratory is hiring a Modeling & Simulation Professional to join the Reactor Systems and Heat Transport team. The role centers on modernizing RELAP5-3D, improving code structure, readability, and maintainability, and integrating new features and tools.

You will perform thermal hydraulic analysis with RELAP5-3D and contribute to a high-impact nuclear safety software platform. The position requires a BS or advanced degree in a relevant field and 2–5 years of experience, with US

Qualifications

• Bachelor’s or advanced degree in a quantitative STEM field from an accredited institution.
• Level 2 or Level 3 prerequisites with specified years of relevant experience.

Responsibilities

• Update legacy Fortran code to modern standards and improve structure.
• Break down complex routines through refactoring and inline documentation.
• Develop new features and algorithms in Fortran and add Python scripts as needed.
• Apply automated documentation systems and streamline updates.
• Submit code updates via pull requests.
• Participate in the International RELAP5 User Group (IRUG) meetings.
• Collaborate with analysts and external partners to support development and integration.
• Perform thermal hydraulic design/safety analysis using RELAP5-3D or similar tools.
• Support strategic planning and performance reviews to align with long-term goals.

Skills

Excellent communication

Fortran programming

Python scripting

Education

B.S. in Mathematics, Engineering, Computer Science or related

Advanced degree in Mathematics, Engineering, Computer Science or related

Tools

RELAP5-3D

Fortran

Python

Job description

Idaho National Laboratory is hiring a Modeling & Simulation Professional to join the Reactor Systems and Heat Transport team. The role centers on modernizing RELAP5-3D, improving code structure, readability, and maintainability, and integrating new features and tools.

You will perform thermal hydraulic analysis with RELAP5-3D and contribute to a high-impact nuclear safety software platform. The position requires a BS or advanced degree in a relevant field and 2–5 years of experience, with US