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Radiant is building the world's first mass-produced, portable nuclear microreactors. The company's flagship product, Kaleidos, is a 1-megawatt, fail-safe microreactor designed for rapid deployment to hospitals, data centers, remote sites, and military bases. Founded in 2020, Radiant is preparing for initial customer deliveries in 2028 and testing its first reactor at Idaho National Laboratory.
As Senior Thermal Engineer, you will own the thermal and CFD analysis for the Kaleidos microreactor, ensuring high fidelity, reliability, and safety across all systems. You will design and develop simulations that inform decisions on reactor systems, cooling, shielding, and multi-physics interactions in a high-temperature gas reactor environment.
Key responsibilities include: executing thermal CFD analysis to evaluate design and performance; developing solutions to model turbulent flow, heat transfer, and multi-physics interactions; identifying and implementing CFD best practices; building automated workflows to expand simulation capabilities and efficiency; and collaborating across interdisciplinary teams to support design of reduced-order analysis methods.
Required qualifications: Bachelor's degree in engineering, physics, or related field; 5+ years of relevant industry experience; 5+ years with commercial CFD codes (STAR-CCM+, Ansys Fluent, or equivalent); proficiency with CAD software (Siemens NX); mastery of finite element and CFD modeling principles; and strong cross-functional communication skills.
Desired qualifications include experience with radiation heat transport modeling, knowledge of nuclear reactor design, and demonstrated self-motivation and ownership. The role requires 100% onsite presence at El Segundo headquarters and willingness to work extended hours as needed to accomplish mission objectives.
Radiant offers substantial equity grants, comprehensive health benefits (medical, dental, vision), 8 weeks paid parental leave, flexible PTO, daily catered lunch, and a collaborative team environment near the Pacific Ocean.
