Senior Mechanical Design Engineer - Cover Gas Systems

As the Responsible Engineer (RE) for the Cover Gas System, you will lead the design, development, testing, and validation of mechanical systems that monitor fission products released from nuclear fuel and maintain an inert reactor core environment. You will own the mechanical architecture of the system, sizing and integrating components that interface with electrical and software subsystems, and collaborating closely across disciplines to define requirements, documentation, and verification plans.

The ideal candidate has a strong background in fluid system design, particularly involving compressible flow, and experience developing hardware for demanding environments. Familiarity with radiation detection technologies (e.g., scintillators, Geiger-Müller counters, or solid-state detectors) is a strong differentiator.

- Design, build, and test the reactor’s cover gas system, hardware, assemblies and detectors.

- Concept and develop custom fluid-dynamic features to support fission product detection and inert environment retention.

- Define design criteria, requirements, system architecture, and verification/validation test plans.

- Collaborate closely with cross-functional teams across thermal, structural, neutronics, controls, and simulation disciplines.

- Engineer components for high-temperature, high-stress, and radiation environments using metals, ceramics, and other advanced materials.

- Perform design-for-manufacturability (DFM) assessments and execute tradeoffs across performance, cost, schedule, and risk.

- Document technical decisions and tradeoffs, and present recommendations to senior leadership.

- 5+ years of experience in full-cycle design engineering roles, including hands-on CAD, analysis, build, and test

- Experience designing, sizing, and integrating fluid systems, preferably involving compressible flow

- Experience performing and interpreting computational fluid dynamics (CFD) analyses.

- Experience in the Nuclear, Aerospace, or Oil and Gas industries

- Experience in a demanding fast-paced development environment

- Experience with design engineering tools such as NX, ANSYS or Femap, and other product lifecycle software

- Experience with engineering scripting languages such as Python and MATLAB

- Ability to work long hours and weekends as necessary to support critical milestones

- The Antares HQ is located in Torrance, CA in a 322,000 square foot, brand new facility featuring large open spaces for team collaboration, R&D, and production, as well as easy access to the 405, 105, and 110 freeways. Our HQ is in the heart of Los Angeles' vibrant emerging tech ecosystem alongside many other high growth startups and enterprises.