Senior Mechanical Engineer (Thermal/Cooling Design)

Summary 

The Senior Mechanical Engineer, Thermal and Cooling Design, is responsible for the thermal engineering and mechanical design of cooling systems for modular data center and industrial applications. This role owns the design process from customer IT load requirements through heat load analysis, cooling architecture selection, equipment sizing, and detailed mechanical design, producing solutions that are efficient, manufacturable, and code-compliant. The engineer works closely with estimating, manufacturing, and electrical and structural engineering to develop standardized cooling products and project-specific designs for high-density AI and HPC deployments. 

Essential Functions and Responsibilities 

Reasonable accommodations may be made to enable individuals with disabilities to perform the essential functions. 

Thermal Analysis 

• Performs thermal and heat load calculations for IT modules at the rack, row, and module level for air-cooled, liquid-cooled, and hybrid deployments 

• Translates customer rack schedules and IT load requirements into cooling capacity, airflow, and water flow requirements 

• Performs psychrometric analysis for supply and return air conditions, dew point control, humidification, and economizer operation 

• Performs heat transfer and fluid flow calculations for coils, heat exchangers, and liquid cooling loops 

• Uses CFD modeling to validate airflow distribution, containment performance, and hot spot risk within modules 

• Performs energy and efficiency analysis (PUE, partial PUE, annualized energy) to compare cooling architectures 

Cooling System Design 

• Develops cooling architectures for high-density AI and HPC loads, including direct-to-chip liquid cooling (DLC), rear door heat exchangers, and in-row, perimeter, and top-mounted air cooling 

• Selects and sizes cooling equipment such as CRAH/CRAC units, fan walls, coolant distribution units (CDUs), chillers, dry coolers, and other heat rejection equipment 

• Designs chilled water and technology cooling system (TCS) loops, including flow rates, delta T, pipe sizing, pressure drop, pump selection, and redundancy configuration (N, N+1, 2N) 

• Designs hot aisle and cold aisle containment and airflow management, including structural containment products 

• Performs air and water balance analyses to confirm that scheduled equipment delivers distributed capacity 

• Develops controls requirements and sequences of operation in coordination with controls engineers 

Product Development and Standardization 

• Develops and maintains standardized cooling configurations and design tools that allow repeatable, fast-turnaround designs across projects 

• Leads development of new cooling products and improvements to existing ones, from concept through prototype, testing, and release 

• Defines test plans and validates performance through factory acceptance testing (FAT) and lab testing 

• Works with manufacturing to ensure designs are optimized for factory assembly, quality, and cost (design for manufacturability) 

• Evaluates new cooling technologies and vendor equipment, and recommends product and process improvements 

Design Documentation 

• Produces mechanical drawings, 3D models, P&IDs, equipment schedules, and bills of material 

• Prepares design basis narratives, technical specifications, product data sheets, and engineering calculation packages 

• Ensures all designs conform to applicable codes and standards, and acts as the company resource on mechanical code analysis 

• Reviews and approves submittals and shop drawings, and authors technical responses to customer RFIs 

• Coordinates mechanical design with electrical, structural, and controls disciplines, and reviews their drawings for impact on mechanical design 

Project and Customer Support 

• Provides mechanical scope, equipment selections, and cost inputs to estimating for customer RFQs and bids 

• Acts as the technical liaison with customers and vendors on cooling design questions and equipment selection 

• Supports commissioning and resolves design-related performance issues identified in the factory or field 

Competencies 

• Functional Knowledge: In-depth expertise in thermal sciences and HVAC/cooling system design, with broad knowledge of related engineering disciplines 

• Business Expertise: Anticipates customer and market needs in high-density cooling; recommends product and design improvements 

• Problem Solving: Solves complex thermal and fluid design problems using analytical and innovative approaches 

• Interpersonal Skills: Communicates complex technical concepts clearly to customers, vendors, and internal teams, including at senior levels 

• Leadership: Leads the technical design of projects with notable risk and complexity 

Required Qualifications 

• Bachelor's degree in Mechanical Engineering 

• 4 to 7+ years of experience in thermal engineering, HVAC design, or data center cooling design 

• Strong knowledge of thermodynamics, heat transfer, fluid mechanics, and psychrometrics 

• Demonstrated experience with hydronic system design and pipe sizing 

• Experience selecting and sizing HVAC or data center cooling equipment 

• Familiarity with ASHRAE TC 9.9 thermal guidelines, ASHRAE 90.4, and applicable mechanical codes 

• Proficiency in 3D CAD (SolidWorks, Inventor, Revit, or similar) and Excel for engineering calculations 

Preferred Qualifications 

• Direct liquid cooling design, including CDU selection and secondary loop design 

• CFD modeling experience (6SigmaDCX, Ansys Fluent, or similar) 

• Refrigeration cycle knowledge (DX, economizers, heat rejection) and coil or heat exchanger selection 

• Experience with a cooling equipment manufacturer or a modular/prefabricated data center builder 

• Product development experience, including prototyping and performance testing 

• PE license or EIT, or actively pursuing 

Work Environment and Physical Demands 

Work is primarily performed in an office environment with significant collaboration across engineering disciplines. Periodic visits to manufacturing facilities and job sites are required. 

Occasional visits to manufacturing facilities and job sites may involve walking active production floors or construction sites and accessing mechanical spaces.