Senior, Thermo-Mechanical Design Engineer - Reactor Cavity Cooling Systems

About the Team

As a Senior Thermo-Mechanical Design Engineer, you will be the Responsible Engineer (RE) for the Reactor Cavity Cooling System (RCCS), leading the design and analysis of a critical deployment system. You will be responsible for the thermal, mechanical, and piping design of the RCCS, ensuring the reactor cavity and surrounding structures remain within design temperature limits, while minimizing wasted thermal power.

This role involves thermal‑fluid analysis, piping and structural sizing, filtration system design, and integration of piping, supports, stacks, and cavity components. The ideal candidate has expertise in thermal‑fluid systems, HVAC, piping, and structural design, and enjoys solving multidisciplinary engineering challenges in a highly constrained design environment.

• Perform thermal-fluid, mechanical, and structural analyses to support the sizing, layout, and optimization of cooling system components, including piping, ducts, stacks, supports, filtration equipment, and reactor cavity structures.
• Define system architecture, operating limits, design margins, and control strategies to ensure reliable performance across all operating conditions.
• Develop design documentation, including engineering calculations, system specifications, interface definitions, design reports, and technical justifications to support licensing and design reviews.
• Support the design, fabrication, and execution of component and system-level testing by developing test articles, test stands, instrumentation plans, and validation procedures to demonstrate system performance and life‑cycle reliability.
• Coordinate cross‑functionally with reactor systems, structures, licensing, manufacturing, procurement, and operations teams to ensure successful integration of the RCCS into the overall plant design.
• Support supplier selection, technical evaluations, design reviews, and resolution of manufacturing and installation issues.
• Present technical work at internal and external design reviews and provide engineering leadership throughout the design, analysis, testing, and deployment lifecycle.

• Bachelor’s degree in Mechanical Engineering, Aerospace Engineering, Nuclear Engineering, or a related engineering discipline with an emphasis on thermal-fluid sciences, heat transfer.
• 5+ years of professional engineering experience in the design, analysis, or development of thermal-fluid, HVAC, heat transfer, or cooling systems.
• Experience performing engineering analyses including thermal, fluid flow, and structural calculations to support component and system design.
• Demonstrated ability to work effectively on multidisciplinary engineering teams and communicate technical concepts to a variety of stakeholders.

• Master’s degree or higher in Mechanical Engineering, Aerospace Engineering, Nuclear Engineering, Thermal Sciences, or a related discipline.
• Experience designing or analyzing natural circulation, buoyancy‑driven, or convective heat transfer systems using CFD or multiphysics simulation tools.
• Demonstrated expertise in HVAC or industrial ventilation system design, including equipment selection, ducting, filtration, airflow management, and system performance testing.
• Proficiency with engineering analysis and simulation tools such as ANSYS, COMSOL Multiphysics, or equivalent finite element (FEA) and computational fluid dynamics (CFD) software.
• Knowledge of materials and structural design considerations, including material selection for heat transfer applications, thermal stresses, creep, corrosion, and environmental degradation.
• Experience designing systems in accordance with ASME Boiler & Pressure Vessel Code, ASME B31 piping codes, or other applicable mechanical and structural design standards.
• Experience serving as a technical lead or Responsible Engineer, coordinating multidisciplinary engineering activities from concept development through testing and deployment.

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

• We are located in Torrance, CA in a 322,000 square foot, brand new facility…