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Mechanical Engineer II

El Segundo, California, United States

Radiant Industries is an El Segundo, CA-based startup developing Kaleidos, a portable, containerized nuclear microreactor. Portable nuclear power with rapid deploy capability can replace diesel generators used today to provide critical asset support for hospitals, datacenters, and military bases or to power microgrids at remote sites. Radiant’s unique, practical approach to nuclear development utilizes modern software engineering to rapidly achieve safe, factory-constructable microreactors leveraging existing, well-qualified materials. Radiant is on a fast track to demonstrate the first fueled operation of a new commercial nuclear reactor design, just two years from now. 

Mechanical Engineer II

Radiant is seeking a highly motivated Mechanical Engineer II to design and develop new hardware systems for the Kaleidos 1MW nuclear microreactor. The ideal candidate takes great ownership of their work end-to-end, is proficient in both design and analysis, and is excited to work in a highly cross-functional, fast-paced environment. You will be a key contributor to building the world's first mass-produced, rapidly-deployable nuclear reactor. 

Responsibilities & Duties  

  • Mechanical Engineering ownership of components and subsystems, such as the following:    
    • Reactor core pressure vessel design per Boiler & Pressure Vessel Code (BPVC).
    • Reactor internal components and mechanisms. 
    • Radiation shielding and thermal insulation. 
    • Heat exchangers and other fluid system components. 
    • Transportation and assembly tooling. 
  • Conduct trade studies and develop designs to meet program requirements.
  • Perform detailed thermal and mechanical analysis (static strength, durability/fatigue) to determine structural integrity (margins of safety) using both 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, manufacturing, and test schedules. 
  • Own risk analysis (FMEA) for subsystems. 
  • Collect requirements, provide expertise and feedback to engineers in other functional areas via clear, constructive communication.  

Required Qualifications & Skills  

  • Bachelor’s degree from an accredited institution in Mechanical, Materials, Aeronautical, Civil or Structural Engineering.  
  • 2+ years of experience conducting trade studies and designing mechanical components or subsystems. 
  • 2+ years of experience performing stress analysis (static and fatigue) using both hand calculations and finite element analysis (FEA) tools (Femap/NASTRAN, Abaqus, or similar).  

Desired Qualifications & Skills  

  • 2+ years of experience with design of multi-component assemblies in CAD (Solidworks or similar). 
  • 2+ years of professional experience designing hardware that was manufactured, deployed, and iteratively improved.  
  • Solid understanding and application of GD&T. 
  • Track record of appropriate selection of analysis fidelity.
  • Ability to derive free-body diagram and control volume-based models for systems.
  • Experience performing CFD analysis (STAR-CCM+ or similar) for combined fluid/thermal modeling of systems.  
  • Self-motivated with strong organizational, written, and oral communication skills.  
  • Experience with using text-based software development tools (Python or similar).

Employee Benefits for Eligible Employees:

  • Stock: Substantial incentive stock plan for all full time, salaried employees.
  • Medical: 100% up to base silver level plan for employee + 50% dependents, offers up to Platinum plans.
  • One Medical: Sponsored memberships for employees and their dependents. 
  • Vision: 100% top tier plan coverage + 50% for dependents.
  • Dental: 100% top tier plan coverage, orthodontia extra, 50% for dependents.
  • Voluntary Life, Accident, Hospital, Critical Illness, Commuter and FSA are offered as employee contributed benefits.
  • Free snacks and drinks onsite. 
  • Flexible PTO policy.

We are an equal opportunity employer and all qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity or expression, pregnancy, age, national origin, disability status, genetic information, protected veteran status, or any other characteristic protected by law.

Unfortunately, we are unable to provide visa sponsorship at this time. This 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.

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