R&D Test Engineer – Fluid Systems & Cryogenic Lab

Commonwealth Fusion Systems LLC; Harvard (MA); On-site; USD 120,000 - 190,000; Full time

Job summary

Commonwealth Fusion Systems LLC in the United States seeks an experienced R&D Test Engineer to design and build fluid systems for test stands supporting magnet testing for SPARC and ARC programs.

You will perform hand calculations, run simulations in ANSYS/COMSOL, and collaborate with production, R&D, and procurement to deliver safe, reliable systems. Strong physics and engineering judgment are essential.

Qualifications

• Bachelor’s degree in mechanical, chemical, process engineering or closely related field.
• 5+ years of experience in engineering of integrated fluid/mechanical systems (large-scale preferred).
• Hands-on experience designing, building, and commissioning fluid systems for specialized environments (cryogenic, vacuum, elevated temperature).
• Experience with ANSYS, COMSOL, 1D flow codes, and system instrumentation.
• Ability to distill complex fluid system details for cross-functional teams (R&D, production, procurement).

Responsibilities

• Design fluid systems for test stands to meet objectives and requirements.
• Develop de-risking strategies and simplifications.
• Perform hand calculations and run ANSYS/COMSOL simulations.
• Procure components, draft specs, and design custom fluid system parts.
• Manage build and commissioning of fluid systems with cross-functional teams.
• Design instrumentation and automation for safe operations.

Skills

Fluid systems design

Hands-on fabrication & testing

Cross-functional communication

Vendor management

System safety

Analytical modeling

Education

Bachelor’s degree in mechanical, chemical, or process engineering

Tools

ANSYS

COMSOL

Python

MATLAB

PFD/P&ID drafting

Job description

Commonwealth Fusion Systems LLC in the United States seeks an experienced R&D Test Engineer to design and build fluid systems for test stands supporting magnet testing for SPARC and ARC programs.

You will perform hand calculations, run simulations in ANSYS/COMSOL, and collaborate with production, R&D, and procurement to deliver safe, reliable systems. Strong physics and engineering judgment are essential.