R&D Test Engineer - Fluid Systems

About the role

The R&D Test Engineer

Fluid Systems at Commonwealth Fusion Systems plays a critical part in the design and execution of advanced test infrastructure necessary for fusion energy development. You will own the development of novel fluid systems for R&D test stands, with a major emphasis on supporting magnet testing and validation activities. The role requires you to manage process fluids that include liquid, gaseous, cryogenic, supercritical, and molten salt media in demanding experimental environments. You will apply strong mechanical and chemical engineering fundamentals to solve complex integration challenges while adhering to strict safety and quality standards. Resourcefulness is essential, combining industry best practices, off-the-shelf and customized hardware, and creative problem solving to deliver fluid systems on aggressive timelines. Projects vary in scale, from smaller test stands and deep system analysis to larger, complex systems required for the SPARC and ARC programs. You will design, build, and commission test hardware, ensuring systems are ready for rigorous testing and data collection. The role involves close collaboration with test and software engineers as well as operations personnel to ensure seamless integration and reliable operation. You will also flex into other disciplines, such as structures and materials engineering, to retire technical risks for SPARC and ARC.

Key facts

What you'll do

• Interpret system requirements and translate them into detailed fluid system designs that support R&D and magnet testing objectives.
• Develop intake paths for process fluids to ensure proper delivery and conditioning for early prototype validation and system verification.
• Design and build customized manifold assemblies capable of handling liquid, gaseous, and cryogenic conditions under demanding test profiles.
• Review system layouts against mechanical limits and safety constraints before fabrication to mitigate risk and ensure compliance.
• Partner with controls teams to create automation sequences that enable steady state testing and precise process control.
• Install sensors and data systems to capture performance metrics during test campaigns, ensuring high fidelity data collection.
• Ship test modules to site locations while maintaining strict quality documentation and traceability for all components and materials.
• Coordinate with production staff to align fabricated parts with project schedules and resolve any manufacturing or integration issues.
• Explore novel materials and design approaches to manage thermal and pressure challenges inherent in fusion environments.
• Collaborate across production, R&D, procurement, and the SPARC team to ensure alignment of fluid systems with program milestones.
• Conduct deep system analysis to identify performance gaps and recommend improvements for larger, complex systems required for SPARC and ARC.
• Commission and validate test hardware, verifying that fluid systems meet functional and safety requirements prior to experimental runs.
• Support test campaigns by maintaining instrumentation, troubleshooting fluid system issues, and implementing corrective actions as needed.
• Document all design decisions, test results, and modifications to create a clear knowledge base for future iterations and scale-up.
• Assist in the development of standardized procedures and checklists to improve consistency and reliability of fluid system operations.
• Participate in cross-functional design reviews and contribute to risk mitigation strategies for technical challenges affecting SPARC and ARC.

Requirements

• Hold a Bachelor's degree in mechanical engineering or a related technical field.
• Possess 3-5 years of experience developing test hardware for industrial applications in demanding environments.
• Demonstrate a strong understanding of fluid dynamics for liquids, gases, and cryogenic states.
• Show the ability to interpret engineering drawings and specify components for complex systems accurately.
• Exhibit effective communication skills to collaborate with cross functional teams in a fast paced, collaborative setting.
• Be comfortable working within structured processes while maintaining flexibility to adapt to changing project requirements.
• Have a proven track record of following through on detailed tasks with attention to accuracy and documentation.
• Be able to work independently and as part of a multidisciplinary team to solve technical challenges.

Nice to have

• Previous experience with high vacuum systems and cryogenic temperature ranges.
• Familiarity with CAD software, test automation frameworks, and data acquisition hardware.
• Knowledge of fusion energy principles and the specific requirements of magnet systems.
• Experience working on large scale experimental programs or high energy physics projects.

Practical notes

Candidates should be available for full time work in Devens, Massachusetts. This role requires the ability to work onsite during critical test and commissioning activities. Travel may be required to support test campaigns at various site locations as determined by project needs. Employment is contingent upon authorization to work in the United States. Candidates must before proceeding to the official apply page to confirm current requirements, duties, pay, and location details for the R&D Test Engineer

Fluid Systems position at Cfsenergy.