Senior Mechanical Design Engineer – Liquid Cooling Systems

About the Company Armada is the hyperscaler for the edge, delivering modular AI infrastructure from first deployment to AI factory with speed, scale and sovereignty. Named one of Fast Company's Most Innovative Companies and to the CNBC Disruptor 50, Armada’s solutions are deployed in over 60 countries globally for organizations ranging from energy to defense. With nearly $500 million in funding to date, Armada is backed by leading investors including Founders Fund, Lux, BlackRock and Microsoft (M12), alongside strategic partnerships with Microsoft, Dell, Palantir, NVIDIA, SpaceX, and Skydio. We are building the infrastructure layer for sovereign and edge AI - rugged, deployable compute for customers that cannot rely on centralized cloud. Working at Armada means taking ownership, driving autonomy, and delivering impact. You’ll tackle challenges that haven’t been solved before and help build something transformative from the ground up. What you do here will not only define your career but help further Armada’s mission to bridge the digital divide for customers around the world. About the Role Armada is seeking a Senior Mechanical Systems / Design Engineer to lead the design and development of liquid cooling and mechanical distribution systems for our modular AI data center platforms. This role sits at the intersection of mechanical design, hydraulic engineering, thermal infrastructure, manufacturing, controls, and commissioning. You will own the mechanical distribution architecture connecting heat-rejection equipment, pumps, piping, manifolds, coolant distribution units, rack cooling systems, and modular interconnects. You will translate system requirements into practical, serviceable, and repeatable designs that can be manufactured in a factory and deployed consistently across multiple sites. This is not a traditional consulting or drawing-review role. You will help establish the design rules, technical standards, interfaces, and commissioning philosophy behind the product itself. What You’ll Own Mechanical and Liquid Cooling Architecture Own the end-to-end mechanical cooling and fluid-distribution architecture for modular data center platforms. Define primary, secondary, and rack-level cooling boundaries. Establish pumping, flow-control, pressure-management, balancing, and redundancy strategies. Align heat-rejection equipment, distribution piping, CDUs, rack manifolds, rear-door heat exchangers, and other cooling interfaces. Develop scalable architectures that support multiple product configurations and deployment sizes. Hydraulic System Design Perform and review pipe-sizing, flow, pressure-drop, pump-head, and system-volume calculations. Develop hydraulic models for water and glycol-based systems. Account for fluid concentration, viscosity, temperature, fittings, valves, strainers, heat exchangers, and equipment pressure losses. Define control-valve, balancing-valve, bypass, minimum-flow, and differential-pressure strategies. Validate system performance across normal, part-load, maintenance, startup, and failure conditions. Mechanical Design and Documentation Own P&IDs, mechanical schematics, equipment schedules, valve schedules, instrumentation schedules, and design calculations. Develop mechanical design criteria, basis-of-design requirements, and standard details. Define clear equipment and scope boundaries between plant systems, modules, CDUs, rack cooling, and field interconnections. Maintain disciplined revision control and technical traceability across the mechanical design package. Review vendor drawings, submittals, calculations, and equipment selections for compliance with system intent. Modular Product Integration Define mechanical interfaces between factory-built modules and field-installed infrastructure. Develop repeatable interconnect strategies for supply and return piping, manifolds, flexible connections, isolation valves, quick disconnects, drains, vents, and leak detection. Establish labeling, connection,…