Reactor Systems Engineer

Ocean Atomics

1d•$95,000 - $220,000

About The Position

The ocean is the largest undeveloped frontier on earth — and the next chapter of abundant energy will be written at sea. We'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 at sea. To 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 As Reactor Systems Engineer, you define the arrangement of the primary system and build the thermal-hydraulic models that prove it works — across normal, transient, and accident conditions, in an environment where ship motion and shock change what "adequate cooling" has to withstand. Your analysis is the throughline between arrangement decisions, safety margins, and the licensing case that lets a reactor operate at sea — work that's core to scaling nuclear energy at sea. This is a role we're hiring at multiple levels (L1 through L4). The work is shared across levels; scope and accountability scale with experience. This work suits someone who treats a thermal-hydraulic model as an argument that has to hold up under scrutiny, not a result to report, and who's energized by translating analysis into real arrangement decisions on a fast-moving design team.

Requirements

Bachelor's degree in Nuclear or Mechanical Engineering, or equivalent practical experience
Experience building and running system thermal-hydraulic models of nuclear plants, with working knowledge of one or more reactor systems codes (e.g. RELAP5-3D, TRACE)
Strong understanding of primary system behavior — natural circulation, two-phase flow, and the tradeoffs between active and passive cooling
Working knowledge of decay heat removal design and the design basis events that size it
Ability to work on a close, rapidly iterative design team and translate analysis into arrangement decisions
Early-career engineers with reactor primary system or thermal-hydraulic analysis exposure through internships, coursework, or early-career roles in the nuclear industry.
Have led thermal-hydraulic analysis or licensing-basis work on at least one reactor primary system design cycle, in commercial nuclear, naval reactors, or comparable regulated environments.

Nice To Haves

Familiarity with multiple system and subchannel/CFD tools (e.g. RELAP5-3D, TRACE, GOTHIC, COBRA, STAR-CCM+) and with coupling system models to neutronics
Experience supporting safety analysis and licensing basis development (DBAs, LOCA/non-LOCA, station blackout)
Strong technical writing skills, particularly for regulator-facing documentation

Responsibilities

Define and maintain the arrangement of the primary system and its interfaces with supporting systems
Build, run, and maintain system thermal-hydraulic models spanning steady-state, transient, and accident scenarios
Analyze decay heat removal architectures and demonstrate adequate cooling for limiting events, accounting for the maritime environment
Couple system models with neutronics and structural inputs to support multiphysics and transient studies
Document analysis results and V&V methodology in support of the licensing process
Provide primary system and accident-response information to our safety analysis, simulator, and operations teams
Lead trade studies that balance arrangement, component sizing, and safety margins across the primary system
Own the licensing basis documentation and justify methodology directly to our regulatory team
Mentor newer engineers and review their thermal-hydraulic analyses
Drive cross-team coupling decisions with our neutronics and structural teams on multiphysics studies