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Senior Fluids Systems Engineer

El Segundo, California, United States

Radiant is an El-Segundo, CA-based clean energy startup building a nuclear microreactor. A climate-friendly alternative to diesel generators, Radiant's Kaleidos 1MW microreactor will be the world's first portable, zero-emissions power source that works anywhere. We plan to test our development reactor by 2026 and if successful, it will be the first new commercial reactor design to achieve a fueled test in over 50 years. Radiant's goal is to bring one of the world's first factory-constructed microreactors to market. Our microreactor can bring power to remote parts of the world and provide backup power for life-saving applications in hospitals or disaster-relief scenarios. 

Senior Fluids Systems Engineer  

Radiant is seeking a highly motivated Senior Fluids Systems 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 thermal and fluids analysis to drive design decisions, verify system performance, and ensure structural 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 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.   
  • Experience with fluid system architecture design.  
  • 3+ years of experience in designing, building, and testing fluids systems.   
  • Proficient knowledge in fluid dynamics and thermodynamics.  
  • Proficient knowledge of heat exchanger design and analysis methods.  

Desired Qualifications & Skills   

  • Knowledge of thermodynamic power cycles.  
  • 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 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.   
  • Takes extreme ownership of work and a high degree of responsibility.   
  • Excellent communication across multidisciplinary teams.   
  • Prior nuclear experience in not required for this role.   

Additional Requirements:

  • Must be willing to work extended hours and weekends as necessary to achieve company goals.
  • Must work 100% onsite at El Segundo HQ.

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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