A novel concept for performance enhancement of immersion-cooled data center servers

Abstract

Efficient thermal management of highly densified data centers is important for carbon-neutral strategies. To this end, this work experimentally explored the most promising single-phase immersion cooling (SPIC) systems. Moreover, it proposed an active performance enhancement technology for SPIC systems. The results indicate that increasing the coolant immersion height helps to improve the SPIC performance, and the resulting increase in flow resistance is negligible. Increasing the volume flow rate improves heat transfer performance while also increasing flow resistance. Moreover, there exists a critical volume flow rate (i.e., 8 L/min) beyond which fails to significantly enhance the SPIC performance. The cooling water temperature is positively correlated with the device temperature but negatively correlated with flow resistance. The micropump-based flow turbulence enhancement and the fan-based flow redistribution techniques reduce the maximum CPU surface temperature by 6.1 % and 5.0 %, respectively. Compared to the micropump method, the fan-based technique degrades the thermal uniformity of coolants but does not significantly increase flow resistance. The economic benefit of the micropump-based strategy is greater for upstream CPUs than downstream CPUs, while the fan-based method is more economically advantageous for downstream CPUs. Moreover, the micropump-based strategy outperforms the fan-based method and demonstrates a 21.39 % increase in energy-economic performance.