Principal Mechanical Design Engineer, Turbomachinery

The role

You will serve as the Responsible Engineer for turbomachinery within a nuclear-driven power generation system. You will own the mechanical architecture, design, and performance of the core rotating assembly for a 1MW closed-loop Brayton cycle.

What you will do

• Serve as Responsible Engineer for the turbomachinery mechanical system
• Own the mechanical architecture and design strategy for high-speed rotating assemblies
• Lead rotor dynamics, structural integrity, and life analysis
• Define and flow down requirements from system-level constraints
• Make technical decisions on rotor layout, shafting, bearings, seals, materials, and clearances
• Lead detailed design of rotors, shafts, housings, and support structures
• Test and validate turbomachinery through model correlation and performance verification
• Perform and review structural and thermal analysis
• Partner with electrical, thermal, and manufacturing teams
• Support assembly, integration, and test of turbomachinery hardware

Required qualifications

• B.S. in Mechanical Engineering or related field
• 10+ years of experience designing high-speed rotating machinery
• Deep expertise in structural analysis and mechanical design of turbomachinery
• Experience with bearings, seals, and high-speed shafting design
• Expert-level proficiency with ANSYS
• Advanced use of NX and Teamcenter
• Strong understanding of tolerancing, GD&T, and precision mechanical assembly
• Experience owning hardware through design, build, and test cycles
• Hands-on experience with assembly, integration, and troubleshooting of turbomachinery
• Strong system-level thinking and mechanical intuition
• Excellent engineering judgment and decision-making capability
• Ability to influence without authority across cross-functional teams

Nice to have

• Experience with closed-loop Brayton cycle systems or similar energy systems
• Familiarity with high-temperature materials and extreme environment design
• Experience integrating mechanical systems with high-speed electric machines
• Prior experience as a Responsible Engineer for complex hardware
• Experience scaling hardware from prototype to production

Benefits

• Substantial incentive stock plan
• Medical: 100% up to base silver level plan for employee + 50% dependents
• One Medical: Sponsored memberships for employees and dependents
• Vision: 100% top tier plan coverage + 50% for dependents
• Dental: 100% top tier plan coverage + 50% for dependents
• Voluntary life, accident, hospital, critical illness, commuter and FSA/HSA
• 8-weeks of paid parental leave
• Additional paid pregnancy leave for CA employees
• Nuclear Engineering Certificate Program with Penn State University
• Daily catered lunch
• Free snacks and drinks
• Flexible PTO policy

Before you apply

• Must be willing to work extended hours and weekends as necessary
• Must work 100% onsite at El Segundo HQ
• Job offer contingent upon capacity to serve in compliance with U.S. export controls

About the company

Radiant is an El Segundo, CA-based company building the world's only mass-produced, transportable nuclear microreactors. Founded in 2020, Radiant is under contract to deliver power to the U.S. Army, Navy and Air Force.