Senior Thermal-Hydraulics Engineer

About the role

Radiant is developing the world’s first mass‑produced, portable nuclear microreactors. We are looking for a Senior Thermal‑Hydraulics Engineer to lead CFD and thermal FEA simulations for our 1‑MW Kaleidos reactor, ensuring high‑fidelity performance, safety, and reliability.

Key responsibilities

• Own and execute thermal CFD analyses of reactor and cooling systems.
• Develop and implement models for turbulent flow, heat transfer, and multi‑physics interactions.
• Identify and apply best practices for CFD simulation accuracy and efficiency.
• Build automated workflows to scale simulation capabilities.
• Collaborate with cross‑functional teams to support reduced‑order analysis methods.

Required profile

• Bachelor’s degree in engineering, physics, or a related field.
• 5+ years of industry experience in CFD/thermal analysis.
• Proven experience with STAR‑CCM+, ANSYS Fluent, or comparable commercial CFD tools.
• Proficiency with Siemens NX or similar CAD software.
• Strong communication skills for cross‑functional collaboration.

Required skills

• STAR‑CCM+
• ANSYS Fluent
• Siemens NX
• Finite element analysis (FEA)
• Computational fluid dynamics (CFD) modeling

What we offer

• Substantial incentive stock plan for all full‑time employees.
• Medical coverage up to a Platinum plan for employee and 50% for dependents.
• Sponsored One Medical membership.
• Opportunity to work on groundbreaking nuclear technology in a fast‑growing startup.