Senior Thermal Engineer, Expeditionary AI / HPC Data Centers

About the Team

The Thermal Engineering team's work is essential to support our rapid innovation cycle and maintain the performance and reliability of advanced defense technologies. Thermal Engineers own the full development life cycle from conceptual design through prototyping, lab and field testing, and operational deployment, ensuring high-performance, resilient systems that meet the demands of complex, contested environments.

About the Role

We are looking for a Senior Thermal Engineer in Costa Mesa, CA to own the thermal management of expeditionary AI/HPC data centers—air-transportable, modular compute and command-and-control infrastructure built to run at forward operating locations. You will apply a deep understanding of heat transfer, fluid dynamics, and HVAC to keep high-density compute running reliably in austere environments with extreme temperatures and limited power.

What You'll Do

• Own the thermal design and analysis of deployable data center cooling systems—air-side and water-side cooling, heat rejection, chilled water plant, and liquid cooling—from rack and chip level up through the full facility.
• Use first principles to discern the right level of analysis, running hand calcs, spreadsheets, and MATLAB/Python first-order models before detailed design.
• Define cooling architecture and heat-rejection strategy—CRAH/CRAC, air-side economization, chilled water plants, dry coolers, CDUs, rear-door heat exchangers, and direct-to-chip and immersion liquid cooling—to keep equipment within limits as power density scales.
• Develop cooling approaches for high-density racks and trade off air, liquid, and hybrid cooling for modular, transportable systems in austere, high-ambient environments.
• Work with electrical, mechanical, and facilities engineers to characterize IT and equipment heat loads across operating and failure modes.
• Weigh cooling architectures against reliability, efficiency (PUE/WUE), and total cost, driving trade studies that balance thermal margin with capital and operating cost.
• Own the thermal FEA/CFD and system models, predict facility performance, and set red/yellow limits for commissioning and operation.
• Lead prototype builds, field testing, commissioning, and operational validation of cooling designs (CAD, sensor and DAQ selection, data post-processing, results).
• Present thermal status at internal and customer reviews with a clear view of timelines and technical status.
• Develop internal tools to improve analysis effectiveness and efficiency.
• Support failure reviews and root-cause analysis with test data and thermal analysis.

Required Qualifications

• MS or higher in mechanical engineering, applied physics, or related field focused on heat transfer, fluid dynamics, and HVAC
• In-depth understanding of heat transfer and fluid dynamics
• 5+ years designing thermal management systems for data centers or comparable mission-critical infrastructure
• Full-spectrum data center thermal experience—air-side and water-side cooling, heat rejection, chilled water plant design, power density management, and liquid cooling
• Steady-state and transient system modeling of thermal management systems, including HVAC and refrigerant simulations
• Validating and testing data center thermal equipment, with knowledge of applicable operating standards
• Track record of staying abreast of the latest data center thermal management technologies
• CAD experience with Siemens NX or SolidWorks

Preferred Qualifications

• Coding in Python or MATLAB for applications such as lumped-capacitance steady-state and transient analysis
• Thermal FEA/CFD experience—STAR-CCM+, ANSYS, Icepak or FloEFD.
• Familiarity with efficiency metrics (PUE/WUE) and thermal design for high-density AI/HPC compute
• Experience with modular, transportable, or ruggedized data centers and operation in austere, high-ambient environments
• Be able to obtain and hold a U.S. Secret security clearance