Senior Thermal Analyst

About the role

Radiant is a fast‑growing startup developing the world’s first mass‑produced, portable nuclear microreactors. As a Senior Thermal Analyst you will lead the thermal CFD and finite‑element analysis for the Kaleidos 1‑MW microreactor, ensuring high‑fidelity simulations that support safety, performance, and rapid commercialization.

Key responsibilities

• Own and execute thermal CFD analyses to evaluate design and performance of reactor, cooling, and shielding systems.
• Develop and implement models for turbulent flow, heat transfer, and multi‑physics interactions.
• Identify and apply CFD best‑practice standards and build automated simulation workflows.
• Collaborate with cross‑functional teams to create reduced‑order analysis methods and support design decisions.
• Provide technical guidance and documentation for simulation results.

Required profile

• Bachelor’s degree in engineering, physics, or a related field from an accredited institution.
• 5+ years of relevant industry experience in thermal analysis.
• 5+ years of hands‑on experience with STAR‑CCM+, Ansys Fluent, or comparable commercial CFD tools.
• Proficiency with Siemens NX CAD software.
• Strong mastery of finite‑element and computational fluid‑dynamics modeling principles.
• Excellent communication skills for cross‑functional collaboration.
• Willingness to work extended hours, weekends, and 100% onsite at the El Segundo headquarters.

Required skills

• STAR‑CCM+
• Ansys Fluent
• Siemens NX
• Computational Fluid Dynamics (CFD)
• Thermal Finite‑Element Analysis (FEA)
• Finite‑element modeling
• Turbulent flow and heat‑transfer modeling
• Multi‑physics simulation
• Automated workflow development
• Radiation heat‑transport modeling (desired)

What we offer

• Substantial incentive stock plan for all full‑time employees.
• Comprehensive medical coverage (100% employee, 50% dependents) with options up to Platinum level.
• Sponsored One Medical memberships for employees and dependents.
• Opportunity to work on groundbreaking nuclear technology with a high‑impact mission.