A system design approach to liquid-cooled microprocessors

This paper describes a compact fluid-cooled computer system, comprised of micro-channel heat exchangers, a fan, and a small pump, to remove heat from a microprocessor. Computational fluid dynamic analysis was used to determine the optimal micro-channel fin array design. Normal flow heat exchanger (NFHX) and parallel flow heat exchanger (PFHX) designs were evaluated. Due to packaging constraints, a micro-channel radiator was used. Integral to the radiator design was the selection of a reliable 30 SCFM blower. Fluid flow and pressure requirements were on the order of 0.5 LPM and 4 PSID respectively. The cooling system developed provided a heatsink to air thermal resistance of 0.155°C/W. An understanding was developed of the effect of airflow, liquid-flow, and heatload on the system performance leading to work which would achieve a heatsink to air thermal resistance of 0.100°C/W and lower.