Radiant
Nuclear
MechanicalProfessionalEngineer(PE)
Neural analysis suggests this role is
optimal for Mid candidates.
“Mechanical Professional Engineer (PE) at Radiant. Skills: Fluid systems engineering, Mechanical design, Thermal analysis, Structural analysis, Piping design. Own critical Kaleidos fluid systems from preliminary design through build and production. Manage primary loop subsystems and power conversion loop”
What You'll Achieve.
Instrumental impact of fueling the first new commercial reactor design in over 50 years by 2026; Deliver first reactor at Idaho National Laboratory this summer; Initial customer deliveries beginning in 2028
Industry & Context.
Perform complex structural & thermal analysis to drive design decisions, verify system performance, and ensure integrity using first-principle hand calculations and finite element tools; Perform trade studies to optimize system and meet program requirements; Own risk analysis (FMEA) for subsystems
Must be willing to work extended hours and weekends as necessary, Must work 100% onsite at El Segundo HQ, Position involves access to technology that is subject to U. S. export controls, Any job offer made will be contingent upon the applicant’s capacity to serve in compliance with U. S. export controls
What They're Looking For.
Must Have
Professional Engineer (PE) Mechanical license, Bachelor’s degree from an accredited institution in Mechanical, Materials, Aeronautical, Civil or Structural Engineering, Experience with fluid system architecture design, 4+ years of experience in designing, building, and testing fluids systems, Proficient knowledge in fluid dynamics and thermodynamics, Proficient knowledge of pressure vessel and piping design and analysis methods
Nice to Have
Knowledge of thermodynamic power cycles, high-temperature material selection & capabilities, and creep-fatigue structural analysis methods, Prior experience with designing piping system for thermal growth using hand calculations and FEA tools, Experience with process piping design and testing codes, such as ASME B31. 3, ASME BPVC Section III & Section VIII, and ASME PCC-2, Prior experience with fluid system modeling via Matlab/Python, Experienced in design for manufacturability and ramping up hardware build in a production environment, Experienced in designing and operating test stands, Prior nuclear experience
What You'll Do.
Own critical Kaleidos fluid systems from preliminary design through build and production
Manage primary loop subsystems and power conversion loop
Perform trade studies
thermal hydraulic analysis
Own end-to-end engineering of fluid systems and components
including compressors
Perform complex structural & thermal analysis to drive design decisions
verify system performance
and ensure integrity using first-principle hand calculations and finite element tools
Develop and execute manufacturing/assembly instructions and test plans
Create and manage a Bill-Of-Materials (BOM)
Find and develop suppliers for all components
Own subassembly design
Own risk analysis (FMEA) for subsystems
How You'll Work.
Team & Collaboration
Provide expertise and feedback to engineers in other functional areas via clear, constructive communication; Excellent communication across multidisciplinary teams
Communication Scope
Clear, constructive communication; Excellent communication across multidisciplinary teams
Process & Methodology
Manage subassembly design, manufacturing, and test schedules, Create and manage a Bill-Of-Materials (BOM)
Full Job Description
ABOUT RADIANT Radiant is an El Segundo, CA-based startup building the world’s first mass-produced, portable nuclear microreactors. The company’s first reactor, Kaleidos, is a 1-megawatt, fail-safe microreactor that can be transported anywhere power is needed and run for up to 5 years without refueling. Portable nuclear power with rapid-deploy capability can replace similar-sized diesel generators and provide critical asset support for hospitals, data centers, remote sites, and military bases. Radiant’s unique, practical approach to nuclear development leverages modern software engineering to rapidly deliver safe, factory-built microreactors that use existing, well-qualified materials. Founded in 2020, Radiant is on track to test its first reactor at the Idaho National Laboratory this summer, with initial customer deliveries beginning in 2028. ABOUT THE ROLE Radiant is seeking a highly motivated Mechanical Professional Engineer to own critical Kaleidos fluid systems from preliminary design through build and production. These systems include the primary loop subsystems and power conversion loop, serving to convert heat from the reactor core into electrical power. You will be responsible for the following: trade studies, component selection, thermal hydraulic analysis, piping design, vendor selection, assembly, and testing. You will have an instrumental impact of fueling the first new commercial reactor design in over 50 years by 2026. Responsibilities & Duties: - Own end-to-end engineering of fluid systems and components, including compressors, valves, and heat exchangers. - Perform complex structural & thermal analysis to drive design decisions, verify system performance, and ensure integrity using first-principle hand calculations and finite element tools. - Perform trade studies to optimize system and meet program requirements. - Develop and execute manufacturing/assembly instructions and test plans. - Create and manage a Bill-Of-Materials (BOM). - Find
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