Thermal​/Hydraulics Engineer

The ocean is the largest undeveloped frontier on earth — and the next chapter of abundant energy will be written 're building the infrastructure to power it.

About Ocean Atomics (OA)

Ocean Atomics is an American company designing, licensing, and assembling a standardized nuclear electric power plant and the surrounding support systems for maritime applications. We will install these plants on any vessel built to our nuclear-ready standards, and will provide end-to-end sustainment in our planned nuclear lifecycle dockyard. We will help develop the licensed operators to unlock this new capability for your energy intensive application  move fast and to lead the creation of this new market, we are leveraging the compact, proven systems enabled by water-cooled reactors.

Our mission

Scale nuclear energy. Power generations.

Our vision

A maritime commons thriving with abundant, economical, modern, and safe nuclear-powered activity — built, serviced, and staffed by re-industrialized American shipyards and people.

Role Summary

The Thermal-Hydraulics engineer performs design and analysis of coolant flowing through the core, primary systems, and safety systems under normal and transient conditions. This role is foundational to the reactor systems design, and the effects of ship motions and ship-driven space constraints demand uncommon levels of innovation and skill.

What You'll Do

• Design and analyze coolant flow through the core and primary systems, evaluating pressure drop, flow distribution, mixing, and heat transfer to optimize performance.
• Develop and refine thermal-hydraulic analysis methods, models, and correlations (e.g., subchannel, system, and CFD analyses) to support core and primary system design.
• Establish thermal margins and operating limits (e.g., DN , flow-induced effects) and feed results into design and safety analyses.
• Partner with the testing team to prioritize test campaigns, define instrumentation and conditions, and target the data most valuable to the design.
• Incorporate test data into analytical models via validating, calibrating, and benchmarking to reduce uncertainty and improve design fidelity.

What You Bring

• Bachelor's degree in nuclear or mechanical engineering required (advanced degree preferred).
• Experience in reactor thermal/hydraulic design and analysis.
• Proficiency with thermal/hydraulic and/or CFD codes (e.g., COBRA, VIPRE, STAR-CCM+, or equivalent).
• Strong grounding in fluid mechanics, heat transfer, and two-phase flow.
• Experience integrating experimental or test data into analytical models.

Export control notice

This role involves access to information subject to U.S. export control laws, including unclassified nuclear technology governed by the U.S. Department of Energy under 10 CFR Part 810. Depending on a candidate's status, access may require DOE authorization, which Ocean Atomics may apply for. Any offer is contingent on your ability to work in compliance with these requirements. We evaluate all applicants regardless of citizenship or national origin, except where required by law.

Why this matters

Every industry on Earth needs scalable, clean energy, and the ocean is the ideal place to unlock it. Joining Ocean Atomics means building real, lasting infrastructure — the kind that powers generations. The world needs abundant energy. Let s make it happen.

Ocean Atomics LLC is an equal opportunity employer.

We are committed to a workplace free of discrimination and do not discriminate on the basis of race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability, genetic information, veteran status, or any other characteristic protected by applicable law. We are committed to providing reasonable accommodations; if you need an accommodation during the application process, contact

Compensation Range: $110K - $240K