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Lead Turbomachinery and Fluid 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. 

Lead Turbomachinery and Fluid Systems Engineer

Radiant is seeking a highly motivated Lead Fluid Systems Engineer to own the development of the Kaleidos power generation cooling loop. You will develop critical hardware at the heart of the supercritical CO2 heat engine while considering for long-term production requirements related to hardware performance, reliability, mass, cost, and manufacturability. The ideal candidate is experienced in building early concept hardware through production, and is excited about our vision to build Earth’s mass-produced nuclear reactors and provide portable clean power to remote areas globally.   

Responsibilities and Duties:   

  • Cradle-to-grave ownership of the Kaleidos secondary cooling loop 
  • Lead a team of engineers responsible for detailed sizing and design of power generation turbomachinery and heat exchangers. 
  • Translate heat engine performance requirements and trade conceptual designs for sCO2 machinery from first article through production. 
  • Work with the responsible engineers of adjacent systems to globally optimize Kaleidos microreactor’s hardware and operations. 
  • Own and maintain performance modeling of the heat engine.  
  • Oversee the build and testing of prototype, first article, and production cooling loop hardware.  

Required Qualifications and Skills:  

  • B.S. in Mechanical Engineering, Aerospace Engineering, Nuclear Engineering, or related discipline.  
  • 5+ years of diversified engineering experience in fluid system, heat exchanger, turbomachinery, and/or mechanism design. 
  • Strong knowledge of turbomachinery and heat exchanger design and build principles.  
  • Proficiency in 1-D fluids modeling of compressible and incompressible flow.  
  • Demonstrated experience in owning end-to-end hardware development cycle, from concept, part design, manufacturing, through build and testing. 
  • Excellent communication and technical documentation skills. 
  • Basic programming knowledge (e.g. Python, C++, or equivalent) 

Desired Qualifications and Skills:   

  • 8+ years of experience and hands-on experience fluid system design, build, and testing. 
  • Experience sizing heat exchangers.  
  • Experience with the supercritical CO2 Brayton cycle.  
  • Experience with gas turbine systems and their operation is a plus.  
  • Experience translating broad machinery requirements (power, speed, bearing leakage) into a conceptual design, including wheel and shaft design, as well as bearing and alternator selection. 
  • Experience optimizing power generation cycles via industry or custom software.  
  • Familiarity with AC power generation and power electronics.  
  • Prior nuclear experience in not required for this role.   

Additional Requirements 

  • Must be willing to work extended hours and weekends as necessary to accomplish our mission. 
  • 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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