Senior Thermofluids Systems Engineer, Power Conversion

You will own thermal CFD analysis for the Kaleidos microreactor, a 1-megawatt portable nuclear reactor targeting rapid deployment. You will use STAR-CCM+ and Ansys Fluent to model turbulent flow, heat transfer, and multi-physics interactions, ensuring high fidelity and safety across reactor systems. Working with cross-functional teams in El Segundo, you will drive simulation workflows and reduced-order methods to accelerate commercialization. This role stands out for its direct impact on the first mass-produced microreactor, with a path to test at Idaho National Laboratory.

You will lead thermal-hydraulics and coupled physics analysis for the Kaleidos microreactor, owning the models that determine heat, coolant, and core interactions under normal and accident conditions. This role sits on the reactor engineering team at Radiant Industries, working alongside reactor physics, mechanical, and safety engineers to support licensing and design trade studies. With a first-of-its-kind reactor moving to test at the Idaho National Laboratory and customer deliveries beginning in 2028, your work directly shapes safety case development for the first mass-produced nuclear reactor. This is a hands-on technical role in a fast-moving startup environment, where your analysis will inform core design and cooling system decisions.

Radiant seeks a driven Senior Thermal Analyst to lead thermal CFD analysis for the Kaleidos microreactor. You will design and execute simulations to ensure high fidelity reliability and safety across reactor systems. This role drives milestones toward commercialization of the first mass-produced nuclear reactor.

Radiant seeks a Senior Nuclear Thermal-Hydraulics Engineer to lead thermal-hydraulics and coupled physics analysis for the Kaleidos microreactor. Own analysis that determines how heat coolant and reactor core behavior interact under normal and accident conditions. This role applies reactor-specific thermal-hydraulics experience to a fast-moving factory-built reactor program. It differs from generic positions by focusing on real-world deployment and licensing support.

You will own electrical systems for our floating PWR reactors from concept through commissioning, shaping the power and control architecture of a groundbreaking marine SMR. Working directly with the Mechanical, Software, Core Design, and Licensing teams, you will design, build, and validate hardware that meets safety-critical standards. This role puts you at the center of the reactor's nervous system, with 5+ years of hands-on experience expected. You will make build vs. buy decisions that directly impact cost, reliability, and deployment speed, helping democratize nuclear energy.

Radiant seeks a Senior Mechanical Engineer (Structures) to design and develop critical structures for the Kaleidos reactor. You will solve challenges creating efficient reliable structures that survive extreme temperatures and meet volumetric constraints. This role impacts fueling the first commercial reactor design in over 50 years by 2026. Ownership of mass-efficient transportable shielding systems container system high temperature graphite and metallic systems. Conduct trade studies develop designs perform thermomechanical analysis dynamic analysis create manufacturing assembly test plans manage bill of materials find suppliers own subassembly design test schedules conduct risk analysis FMEA provide expertise communicate with cross functional teams.