A novel integrated flat thermosyphon heat sink for energy-efficient chip-level thermal management in data centers

A novel Integrated Flat Thermosyphon Heat Sink (IFTHS) with enhanced performance is developed in the present study. The IFTHS has a condenser with integrated hollow fins wherein the inner surface of the hollow fins is used for condensation, and the outer surface is used for air-side convective cooling. The thermal performance of the IFTHS is investigated at different filling ratios to find the best-performing filling ratio. The thermal performance of the IFTHS is improved further through an evaporator with minichannels and superhydrophobic condenser. Superhydrophobic condenser improved the performance by 16 % due to quicker condensate return and dropwise condensation. Minichannel evaporator improved the performance by 19 % due to enhanced pool boiling from improved bubble dynamics and increased surface area. The combination of a superhydrophobic condenser and minichannel evaporator improved the performance by 36 %. The overall resistance, maximum temperature, and heat sink weight are reduced by 19-41 %, 8-25 degrees C, and 44-46 % with IFTHS configurations compared to the baseline conventional flat thermosyphon having a condenser with solid fins. The electronic component lifespan can be increased by 3.73-17.75 times, and the room air cooling load can be reduced by 8.04-25.12 kJ/kg when the IFTHS configurations are used for cooling electronic chips in data center servers instead of the baseline configuration. Thus, the novel IFTHS configurations developed in the present study can contribute to energy efficient chip-level thermal management in energy-intensive data centers.