Senior Thermal Analyst

Xcimer Energy builds on decades of research in Inertial Fusion Energy (IFE), combined with a groundbreaking new laser architecture, to accelerate the deployment of fusion power plants. Our mission is to deliver clean, limitless fusion energy fast enough to meet global decarbonization goals. Xcimer has assembled a world-class team spanning tough tech, fusion science, and advanced manufacturing, with a proven track record of rapid execution. Backed by leading investors, we are uniquely positioned to bring inertial fusion power from prototype to reality. Join us in powering a better world with fusion.

This is a full-time, onsite role based at our headquarters in Denver, CO.

As Senior Thermal Analyst, you will lead the thermal and CFD analysis across Xcimer’s Energy and Defense programs. You will evaluate cooling architectures, analyze steady-state and transient heat loads, and provide thermal insight that drives system-level design decisions. You will work closely with design engineers and fellow analysts to ensure thermal behavior is fully integrated into cross-disciplinary workflows including component design, architecture trades, performance optimization, and experimental validation. You will generate traceable analysis documentation, participate in peer reviews, and provide analysis guidance to design engineers and junior analysts. As hardware progresses from prototype to integrated testing you will support troubleshooting, test correlation, and rapid iteration. We are looking for engineers who enjoy building systems from concept through commissioning and thrive in fast-paced manufacturing environments.

Responsibilities

• Lead thermal and CFD analyses for cooling systems, gas-flow pathways, and fusion chamber components.
• Build and maintain transient and steady-state thermo-fluid models including conduction, convection, radiation, turbulent flow, and compressible gas dynamics.
• Validate CFD and thermal models using analytical techniques, experimental data, and multi-physics correlations.
• Produce clear, accurate, and traceable analysis documentation for design reviews, architecture trades, and test readiness.
• Conduct peer reviews of thermal/CFD analyses from other analysts; maintain best practices for modeling, assumptions, margins, and documentation.
• Collaborate with analysts and design engineering teams to ensure thermal results are fully integrated into component and system designs.
• Support prototype builds and test operations by diagnosing thermally-related issues, supporting root-cause investigations, and recommending corrective actions.
• Contribute to the development of internal thermal/CFD workflows, correlation standards, and analysis verification/validation processes.

Qualifications

• Education: B.S. in Mechanical Engineering, Aerospace Engineering, Nuclear Engineering, or related field.
• Experience: 8+ years of thermal-fluid, CFD, or heat-transfer analysis experience supporting engineered hardware (Energy, Aerospace, Laser Systems, HVAC.).
• Expert proficiency with commercial CFD tools (e.g., STAR-CCM+, Ansys Fluent) and experience with CFD verification/validation.
• Demonstrated experience with turbulent flow modeling, compressible and incompressible fluids, convection and radiation heat transfer, and cooling system design.
• Strong fundamentals in classical heat transfer and thermo-fluids, including hand calculations and closed-form thermal analysis methods.
• Demonstrated experience supporting hardware test campaigns, thermal instrumentation, flow diagnostics, and correlating models with experimental data.
• Must be a U.S. citizen or national, U.S. permanent resident (Green Card holder), or lawfully admitted into the U.S. as a refugee or granted asylum.

Desired

• M.S. or advanced degree in Mechanical Engineering, Aerospace Engineering, Nuclear Engineering, or related field.
• Hardware selection and/or design experience: fans, pumps, heat exchangers, piping, and other supporting equipment.
• Experience developing multi-physics simulation environments involving thermal, flow, mechanical stress using simulation tools (SimCenter, COMSOL, Abaqus, etc.).
• Experience with high-temperature systems, transient pulsed heat deposition, gas lasers, or fusion-related thermal environments.
• Familiarity with engineering materials, manufacturing processes, cooling strategies, and how they affect thermal performance and reliability.
• Familiarity with scripting languages (Python, MATLAB, VBA) for automating workflows and post-processing results.

  CAD/PLM experience (NX, Teamcenter).