Radiant
Nuclear Reactor
ThermalModelingEngineer(CFD)
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“Thermal Modeling Engineer (CFD) at Radiant. Skills: CFD, Thermal FEA, Star CCM+, Ansys Fluent. Develop and execute thermal analysis and CFD. Evaluate design and performance of Kaleidos systems”
What You'll Achieve.
Ensure high fidelity, reliability, and safety of our systems; Inform decisions across reactor systems, cooling systems, shielding, and more; Drive milestones forward to unlock commercialization
Industry & Context.
Build confidence in lower-fidelity thermal analysis methods
Willing to work extended hours and weekends as necessary, Work 100% onsite at El Segundo HQ, Compliance with U.S. export controls
What They're Looking For.
Must Have
Bachelor's degree in engineering, physics, or similar field from an accredited institution, Experience with Star CCM+ or Ansys Fluent, Proficiency with CAD software (Siemens NX), Understanding of finite element and computational fluid dynamics modeling principles and methods, Ability to effectively communicate with cross-functional teams
Nice to Have
Experience with radiation heat transport modeling, Knowledge of nuclear reactor design, Driven, self-motivated, and takes ownership of work end to end
What You'll Do.
Develop and execute thermal analysis and CFD
Evaluate design and performance of Kaleidos systems
Document analysis results
Expand CFD capabilities
Produce analysis geometry from mechanical design CAD
Develop methods and calculations for thermal analysis
How You'll Work.
Team & Collaboration
Effectively communicate with cross-functional teams; Work in an interdisciplinary environment
Communication Scope
Effectively communicate with cross-functional teams; Communicate clear and actionable outputs
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. Thermal Modeling Engineer (CFD) Radiant is seeking a driven Thermal Modeling Engineer with expertise in CFD and thermal FEA modeling. You will design, develop and implement simulations for the Kaleidos microreactor to ensure high fidelity, reliability, and safety of our systems. You’ll work on cutting edge technical problems for a high temperature gas reactor that inform decisions across reactor systems, cooling systems, shielding, and more. You will have an opportunity to work in an interdisciplinary environment and drive milestones forward to unlock commercialization of the first mass-produced nuclear reactor. Responsibilities and Duties: - Develop and execute thermal analysis and CFD to evaluate design and performance of Kaleidos systems. - Document analysis results to communicate clear and actionable outputs. - Expand CFD capabilities, accuracy, and efficiencies via methods and workflow development projects. - Produce analysis geometry from mechanical design CAD - Develop methods and calculations to support and build confidence in lower-fidelity thermal analysis methods. Required Qualifications and Skills: - Bachelor’s degr
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