Lead Multi-Physics Simulation Engineer

Commonwealth Fusion Systems LLC; Milpitas (CA); On-site; USD 146,000 - 210,000; Full time

Benefits offered by this job

Competitive compensation with equity

13 Company-wide Holidays

Flexible vacation days

10 sick days

Generous parental leave policy

Health, dental, and vision insurance

401(k) with employer matching

Professional growth opportunities

Team-building activities

Job summary

Commonwealth Fusion Systems LLC in Milpitas, California, is seeking a Senior Modeling and Simulation Engineer to lead multi-physics simulations for next‑gen fusion hardware. You will model thermal, structural, fluid, and chemical interactions and guide design decisions.

The role requires 7+ years of R&D simulation experience, mastery of ANSYS or COMSOL, and the ability to validate virtual models with physical test data. Equity, strong benefits, and a fast-paced, mission-driven environment.

Qualifications

• Master’s or PhD in Mechanical/Aerospace Engineering or Physics with computational mechanics focus.
• 7+ years of experience in simulation and predictive analysis of complex R&D systems.
• Expert in ANSYS, COMSOL Multi-physics, or equivalent high-end FEA/CFD tools.
• Proven ability to run coupled simulations (fluid-structure, thermal-structural, chemical).
• Ability to validate virtual models with physical test metrics (strain, thermal imaging, flow sensors).

Responsibilities

• Execute advanced FEA and CFD for processing equipment.
• Build, run, and evaluate highly coupled simulations covering structural mechanics, high-temperature thermal management, fluid/gas flow dynamics, and chemical reaction kinetics.
• Implement engineering workflows for simulation data management, mesh convergence criteria, and rigorous verification and validation using physical test data.
• Provide analytical leadership during technical design reviews, verifying margins and distributions to guide design choices.
• Collaborate with Mechanical Designers, Electrical Engineers, Materials Scientists, and Chemical Specialists to translate insights into hardware modifications.
• Own and report on modeling milestones, timelines, and computational resources to stakeholders.

Skills

7+ years of experience in simulation &

Multi-physics modeling

Empirical correlation

Education

Master’s or PhD in Mechanical/Aerospace Engineering or Physics

Tools

ANSYS

COMSOL Multi-physics

Job description

Commonwealth Fusion Systems LLC in Milpitas, California, is seeking a Senior Modeling and Simulation Engineer to lead multi-physics simulations for next‑gen fusion hardware. You will model thermal, structural, fluid, and chemical interactions and guide design decisions.

The role requires 7+ years of R&D simulation experience, mastery of ANSYS or COMSOL, and the ability to validate virtual models with physical test data. Equity, strong benefits, and a fast-paced, mission-driven environment.