Propulsion Engineer II, Thermal Systems

Application close date:
Applications will be accepted on an ongoing basis until the requisition is closed. At Blue Origin, we envision millions of people living and working in space for the benefit of Earth. We’re working to develop reusable, safe, and low-cost space vehicles and systems within a culture of safety, collaboration, and inclusion. Join our team of problem solvers as we add new chapters to the history of spaceflight!

This role is part of the Blue Origin Engines business unit, where our focus is the design, development, manufacturing, and testing of engines and propulsion systems. Built for multiple uses, our family of engines is powering the next generation of rockets for commercial, civil, national security, and human spaceflight. As part of a hardworking team of engineers, you will design, analyze, and optimize the next generation of heat exchangers for demanding thermal‑fluid environments.

You will work with cross‑functional teams to develop innovative, high‑effectiveness, low‑pressure‑drop thermal solutions and to mature them from concept through qualification. You will be responsible for defining heat exchanger cores, headers, manifolds, and assemblies to support fabrication, testing, and production. A successful candidate will apply their knowledge across multiple applications involving heat transfer between fluids and phases, demonstrating versatility and technical depth as designs advance through successive iterations.

Relocation provided Travel expected up to 20% of the time.

• Lead design, development, and testing of heat exchangers and related thermal‑fluid systems, driving successive design iterations toward improved effectiveness, cost, and manufacturability
• Develop system requirements, specifications, and design documentation for heat exchanger cores and assemblies
• Design and optimize heat exchanger geometries and components — including cores, headers, manifolds, tube sheets, and mounting/support structures — balancing thermal effectiveness against pressure drop, mass, and volume
• Select appropriate materials for applications considering thermal cycling, creep, fatigue, and corrosion resistance
• Create detailed engineering drawings and models using 3D CAD software with proper GD&T per ASME Y14.5 standards
• Lead and participate in component and system‑level testing, including test planning, execution, and thermal/hydraulic data reduction and correlation to analytical predictions
• Troubleshoot design and operational issues (e.g., thermal stress, flow maldistribution, fouling, leakage) with calculated risk assessment
• Collaborate with manufacturing and quality teams to ensure producibility of designs, including brazed, welded, and additively manufactured cores
• Interface with various engineering disciplines to ensure proper thermal and system integration

• Bachelor's degree in Mechanical Engineering or related field
• Minimum of 2 years of relevant industry experience
• Strong application of first principles in heat transfer, fluid mechanics, thermodynamics, and materials science
• Experience with heat exchangers, high‑temperature or cryogenic thermal systems, or high‑pressure fluid systems
• Knowledge of thermal expansion management and thermal stress analysis
• Experience with test data analysis and correlation of test results to predictions
• Solid troubleshooting skills for complex thermal‑fluid systems
• Familiarity with relevant industry standards and codes (ASME BPVC, TEMA, API, etc.)
• Must be a U.S. citizen or national, U.S. permanent resident (current Green Card holder), or lawfully admitted into the U.S. as a refugee or granted asylum.

• Master's degree in Mechanical Engineering with focus on thermal sciences or fluid systems
• 5+ years of relevant industry experience
• Experience designing and iterating on multiple heat exchanger types (e.g., tube‑and‑shell, plate‑fin, printed‑circuit/PCHE, regenerative cooling channels, cryogenic and tank‑pressurization heat exchangers)
• Working knowledge of heat exchanger sizing and rating methods (LMTD/ε‑NTU), pressure‑drop optimization, and flow distribution
• Familiar with CFD and FEA simulation tools for…