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Radiant
El Segundo, CA, USA
USD 200,500-314,475 / year + Equity
El Segundo, CA
Full time
On-site
EngineeringMechanical Engineering
Principal Turbomachinery Engineer
Radiant is seeking a Principal Turbomachinery Engineer to serve as the Responsible Engineer for the turbomachinery within our nuclear-driven power generation system. This role owns the mechanical design, integrity, and performance of the core rotating assembly at the heart of our 1MW closed-loop Brayton cycle.
You will define and drive the mechanical architecture of high-speed rotating hardware operating at extreme temperatures, pressures, and rotational speeds. As a deeply technical individual contributor, you will set direction for rotor dynamics, structures, bearings, seals, and system integration while working closely with electrical, thermal, and manufacturing teams.
This is a hands-on, high-ownership role focused on technical excellence, sound engineering judgment, and delivering reliable, production-ready turbomachinery.
Responsibilities
Technical Ownership & System Architecture
Serve as Responsible Engineer for the turbomachinery mechanical system
Own the mechanical architecture and design strategy for high-speed rotating assemblies (up to ~30 krpm)
Lead rotor dynamics, structural integrity, and life analysis for rotating components and assemblies
Define and flow down requirements from system-level constraints including thermal, structural, and operational environments
Make key technical decisions on rotor layout, shafting, bearings, seals, materials, and clearances
Ensure designs meet performance, reliability, safety, and regulatory requirements
Establish and uphold standards for mechanical design rigor, analysis quality, and documentation
Mechanical Design & Analysis
Lead detailed design of turbomachinery components including rotors, shafts, housings, and support structures
Test and validate rotordynamic systems, driving model correlation, risk reduction, and performance verification
Perform and review structural and thermal analysis to ensure integrity under high-speed and high-temperature operation
Define tolerances, fits, stack-ups, and alignment strategies for precision rotating assemblies
Partner with electrical engineering on alternator rotor integration, including electromagnetic and structural coupling
Cross-Functional Integration
Partner closely with turbomachinery aero, motor design, thermal, manufacturing, and test teams
Ensure seamless integration between turbine, compressor, and alternator subsystems
Drive clear interface definitions across mechanical, electrical, and thermal boundaries
Collaborate with manufacturing to ensure designs are producible, inspectable, and scalable
Engage with suppliers on technically critical components and design decisions
Prototyping, Testing & Validation
Support assembly, integration, and test of turbomachinery hardware
Define validation strategies including spin testing, thermal testing, and system-level operation
Lead root cause analysis and drive design iteration for test failures or performance gaps
Remain hands-on in hardware bring-up, troubleshooting, and refinement
Technical Influence
Act as a subject matter expert in turbomachinery mechanical design and rotating systems
Provide technical guidance and design reviews across the team without direct people management responsibility
Influence engineering direction through deep expertise, data-driven decisions, and strong judgment
Contribute to technical roadmap, risk identification, and mitigation strategies
Required Qualifications
B.S. in Mechanical Engineering or related field
8+ years of experience designing high-speed rotating machinery (turbines, compressors, or similar systems)
Deep expertise in structural analysis and mechanical design of turbomachinery
Experience with bearings, seals, and high-speed shafting design
Expert-level proficiency with analysis tools (e.g., ANSYS) and advanced use of NX and Teamcenter for complex design, simulation, and product lifecycle management
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
Clear communicator capable of articulating complex technical concepts
High ownership mindset and accountability for hardware outcomes
Ability to operate effectively in a fast-paced, first-of-a-kind development environment
Preferred Qualifications
10+ years of turbomachinery or rotating equipment experience
M.S. or Ph.D. in Mechanical Engineering
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
Additional Requirements
Must be willing to work extended hours and weekends as necessary to accomplish our mission
Must work 100% onsite at El Segundo HQ
Stock: Substantial incentive stock plan for all full-time employees.
Medical: 100% up to base silver level plan for employee + 50% dependents, offers up to Platinum plans.
One Medical: Sponsored memberships for employees and their dependents.
Vision: 100% top tier plan coverage + 50% for dependents.
Dental: 100% top tier plan coverage, orthodontia extra, 50% for dependents.
Voluntary life, accident, hospital, critical illness, commuter and FSA/HSA are offered as employee contributed benefits.
8-weeks of paid parental leave for all parents. Additional paid pregnancy leave for CA employees.
Daily catered lunch. Free snacks and drinks.
Flexible PTO policy. Remote workday allocation.
Company and team-bonding events, happy hours and in-person camaraderie.
Beautiful El Segundo headquarters close to the Pacific Ocean.
Total Compensation and Benefits
Radiant compensates people for impact and invests in those who continue to raise the bar. Radiant’s new hire compensation package includes base salary, substantial equity grants, and comprehensive health benefits. Total compensation and level are determined through a rigorous evaluation of interview performance, experience, education, and qualifications, and are designed to support continued growth as scope, responsibility, and impact expand at Radiant.
The best of today’s advanced reactor builders don’t wait for job postings. They join the winning team. If that’s you, contact us directly for immediate opportunities: [email protected].
We are an equal opportunity employer and all qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity or expression, pregnancy, age, national origin, disability status, genetic information, protected veteran status, or any other characteristic protected by law.
Unfortunately, we are unable to provide visa sponsorship at this time.
This position involves access to technology that is subject to U.S. export controls. Any job offer made will be contingent upon the applicant’s capacity to serve in compliance with U.S. export controls.
Compensation Range: $200,500 - $314,475