Liquid Cooling Mechanical Engineer

Accelsius LLC; Austin (TX); On-site; USD 110,000 - 160,000; Full time

Benefits offered by this job

Equity

Full benefits

401k

Flexible PTO

Job summary

Accelsius LLC is seeking a Liquid Cooling Mechanical Engineer to design server-level liquid cooling hardware for AI and HPC platforms, including cold plate loops, tubing, manifolds, and pressure-containing assemblies.

The role progresses from prototype to production release, translating thermal prototypes into manufacturable hardware while collaborating with R&D technicians and suppliers. You will lead design reviews and mentor junior engineers, ensuring manufacturability and performance.

Qualifications

• Bachelor’s degree in mechanical engineering or similar required.
• 5+ years of progressively responsible experience.
• Direct experience designing liquid cooling hardware for data center servers or racks.
• Design of pressure-containing fluid systems: joint design, fitting selection, material selection, pressure rating, and leak testing.
• Working knowledge of fluid mechanics and heat transfer; CFD and thermal specialization not required.
• Proficiency in a parametric 3D CAD tool (SolidWorks preferred) and producing manufacturing drawings with GD&T.
• FEA experience evaluating deformation and stress in mechanical parts.
• Record of taking designs through fabrication and release with external suppliers.
• Startup experience is a plus.

Responsibilities

• Design and CAD work from prototype to production release, including cold plate loops, tubing, manifolds, and fittings.
• Lead design reviews and mentor early-career engineers on server plumbing design.
• Produce production-ready 3D models, drawings with GD&T, and BOMs; manage revisions via ECOs in PLM.
• Work with suppliers and fabricators from RFQ through first article; drive DFM.

Skills

Ownership

Clear communication

Cross-functional collaboration

FEA

GD&T

CFD (non-specialized)

Education

Bachelor's degree in mechanical engineering

Tools

SolidWorks

GD&T

FEA

Job description

Interested in getting in at the ground floor of a new, disruptive company attacking an important multi-billion-dollar problem? Businesses and consumers continue to demand increasing data services at an exponential rate -- streaming, deep learning, analytics, loT connectivity, and more. What this means is higher performing CPUs, components, servers, and ultimately Data and Edge computing centers, all generating excessive heat that is increasingly difficult to manage with traditional cooling systems. Accelsius is developing revolutionary direct-to-chip, 2-Phase cooling technologies that empower and enable Server OEMs, Data Centers, and Edge Computing Operators, to meet performance, sustainability, scale, and cost goals while serving this high-growth market for data services.

Accelsius is looking for a Liquid Cooling Mechanical Engineer to design server-level liquid cooling hardware for AI and HPC platforms: cold plate loops, server plumbing, manifolds, and the pressure-containing assemblies that connect them. This engineer will take designs from first prototype through production release, translating thermal engineers’ prototypes into manufacturable hardware, and will work alongside our R&D technicians to validate them in the lab. This position will report directly to the Server Cooling Product Manager and the right candidate will be hands-on, self-directed, and comfortable owning a design across engineering, manufacturing, suppliers, and customer teams.

Role Responsibilities

Design and CAD (70%)

• Review thermal engineers’ concept and first-prototype designs to confirm a path to manufacturability
• Translate first-prototype server liquid cooling assemblies for GPU and CPU platforms into production-ready designs, including cold plate loops, tubing and hose routing, manifolds, fittings, and quick disconnects, within the space, serviceability, and interface constraints of OEM server chassis
• Design pressure boundaries: select materials, joining methods, and fittings; establish design, proof, and burst pressures; confirm compatibility with the working fluid
• Partner with thermal engineers on plumbing sizing, pressure drop, and flow distribution, contributing packaging constraints, component selection, and manufacturability input to their analysis
• Perform FEA to evaluate deformation and stress in pressure-containing parts and assemblies
• Produce production-ready 3D models, drawings with GD&T, and BOMs; manage revisions through ECOs in our PLM system
• Work with cold plate suppliers, braze shops, and fabricators from RFQ through first article; drive DFM and resolve supplier issues
• Lead design reviews and mentor early-career engineers on server plumbing design
• Support OEM and customer engagements with integration drawings and interface specifications

Test and Validation Support (30%)

• Define test requirements and acceptance criteria for pressure, leak, flow, and pressure drop testing
• Define requirements for test fixtures and hardware, and review the manufacturing team’s fixture designs against them
• Support R&D technicians in building and running tests on our R&D test rigs
• Review test data, lead root cause investigations on failures, and carry findings into the next design revision

Qualifications For This Role Include

• 5+ years of experience with progressively increasing responsibility
• Bachelor’s degree in mechanical engineering or similar required
• Direct experience designing liquid cooling hardware for data center servers or racks required (single-phase or two-phase)
• Demonstrated design of pressure-containing fluid systems: joint design, fitting selection, material selection, pressure rating, and leak testing
• Working knowledge of fluid mechanics and heat transfer sufficient to collaborate with thermal engineers on sizing and performance; CFD and thermal specialization not required
• Proficiency in a parametric 3D CAD tool (SolidWorks preferred) and producing manufacturing drawings with GD&T
• FEA experience evaluating structural deformation and stress in mechanical parts
• Record of taking designs through fabrication and release with external suppliers
• Takes ownership, communicates clearly, and works across disciplines
• Startup experience is a plus

Preferred Experience

• Working with cold plate vendors and brazing manufacturers
• HVAC, refrigeration, or hydronic systems design
• Cold plate and fluid-component manufacturing processes: brazing, skiving, friction stir welding, machining
• Familiarity with OCP liquid cooling specifications, ASHRAE liquid cooling guidelines, and IEC/UL 62368-1 requirements for liquid-filled components
• ECO and configuration management in a PLM system

• competitive salary with equity, a full range of benefits including medical and dental, 401K, and flexible PTO.

The position is based in Austin, Texas.

This position includes the responsibilities outlined above and may also encompass additional duties as assigned to meet business and compliance needs.

Accelsius does not discriminate on the basis of race, color, religion, sex, sexual orientation, gender identity or expression, national origin, age, disability, veteran status, marital status, or based on an individual's status in any group or class protected by applicable federal, state or local law. Accelsius encourages applications from minorities, women, the disabled, protected veterans, and all other qualified applicants.