Design and Modeling of a High Reliability Pump for Liquid Cooling Data Center Servers

Abstract

Data center buildings are tasked with safely housing a large number of temperature sensitive components found in computer servers. These industrial buildings consume about 1.3% of the world’s electrical energy, of which about 40% is spent on cooling [1, 2]. Current cooling strategies fail to meet the heat transfer requirements of current microprocessors due to high heat fluxes resulting from increased component density and decreased device size. The goal of this study is focused on the design and modeling of a high-reliability pump that can be used at the data center server board-level source of the heat flux. The design includes a shaft-less pump design, an external magnetic drive, and a self-adjusting position of the rotor driven by a herringbone grooved fluid bearing. A proof-of-concept prototype of the design was built and tested using a flow meter. The manufacturing of the pump’s rotor, chassis, and stator was all accomplished using the Fused Deposition Modeling three-dimensional (3D) printing technique. Best practices for the dimensional accuracy of 3D printed herringbone groove geometries are revealed for both plastic and composite filament material. The electrical properties of composite metal filament are also discussed. The anticipated benefit of this project is to increase the use of liquid cooling used in data center servers replacing passive air-cooled heat sinks. By doing this a large reduction in the overall electrical power consumption currently required by data centers can be achieved.