About the role

Aalo Atomics is seeking a Thermal-Hydraulics Engineer to join our nuclear engineering group and play a key role in advancing the thermal-fluid modeling, design, and testing of our liquid-metal-cooled reactor. This role requires deep understanding of system-level thermal-hydraulic behavior, passive safety principles, and advanced modeling tools such as RELAP5-3D, SAM, and subchannel or CFD codes.

The selected candidate will work closely with our core design, systems engineering, and safety analysis teams to develop and implement detailed thermal-fluid models, support component and system testing efforts, and drive performance improvements across design iterations.

What you'll do

• Apply nuclear and mechanical engineering principles to design, model, and evaluate thermal-fluid behavior in sodium-cooled reactor systems.
• Develop and maintain steady-state and transient models using RELAP5-3D, SAM, or similar codes to assess system behavior under normal, off-normal, and accident conditions.
• Perform CFD simulations of subchannels and other reactor systems using ANSYS-FLUENT, CTF, STAR-CCM+, or equivalent CFD commercial software.
• Support development of testing plans and analysis for the Aalo sodium test facility and related component-level experiments.
• Work collaboratively across engineering disciplines to integrate thermal-hydraulic models into safety analyses, component design, control strategy, and system validation.
• Review applicable thermal-hydraulic codes, identify gaps in predictive capability, and recommend improvements aligned with industry advancements.
• Support preparation of technical documentation including analysis reports, test plans, and design review packages.

Qualifications

• Education: BS+ in Nuclear Engineering, Mechanical Engineering, or related field with a thermal-fluids focus.
• Experience: 3–10 years of experience in thermal-hydraulic modeling and simulation, preferably with sodium or other liquid metal reactors.
• Technical Skills:
• • Strong proficiency in RELAP5-3D, SAM, TRACE, or similar system codes.
  • Experience with subchannel or CFD tools (e.g., CTF, STAR-CCM+, OpenFOAM).
  • Familiarity with MOOSE-based applications (e.g., PRONGHORN, BISON) is a plus.
  • Proficient in scripting and data analysis (e.g., Python, MATLAB).
  • Experience modelling liquid metal systems and any low Prandtl number system.
  • Strong familiarity with requirements for verification and validation for nuclear applications.
• Professional Traits:
• • Effective communicator and technical problem solver.
  • Comfortable working in fast-paced, multidisciplinary environments.
  • Demonstrated ability to document results, lead technical efforts, and meet project milestones.