Managing 1000 W high-power chips by a High-Capacity and lightweight 3D thermosyphon: An experimental and theoretical study

The digital economy raised a rapid demand for computing power, leading to an urgent need for thermal management of high-power chips. Although the liquid cooling technology was efficiency, it also had the disadvantages of liquid leakage risk and high cost. In this study, using the environmentally friendly refrigerant R1233zd(E) as working fluid, a lightweight aluminum-based 3D thermosyphon which combined the advantages of air cooling and phase-change was proposed and tested. The micro structures were fabricated on the heat absorption side and heat releasing side of the 3D thermosyphon to enhance its overall performance, which enabled the 3D thermosyphon to manage the heat of high power and high heat flux chips. The results indicated that the liquid filling ratio of the 3D thermosyphon had an optimum value of 42 %. Comparing to plain surface, the micro-pin fins on the heat absorption side enhanced the boiling heat transfer dramatically, leading to a decreasing of thermal resistance of 16.8 %. Besides expanding the boiling chamber volume, the issue of vapor diffusion at high heat fluxes was addressed, which enabled the 3D thermosyphon to achieve a recorded heat flux of 112 W/cm² and a maximum cooling power of 1000 W. Finally, considering the boiling, condensation, and forced convection heat transfer process, a comprehensive predicting model for the 3D thermosyphon was developed and agreed well experimental results.