Staff Turbomachinery Engineer

About the Role

Radiant is seeking a Staff 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 & Duties:

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 & Skills:

• 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.

Desired Qualifications & Skills:

• 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.

Benefits and Perks

• Stock: Substantial incentive stock plan for all full-time employees.

• Daily catered lunch. Free snacks and drinks.

• Flexible PTO policy. Remote workday allocation.