Study on the thermal performance of three-dimensional oscillating heat pipe with super-hydrophobic/super-hydrophilic surface for thermal management application

The current trend of miniaturization and integration of power chips poses significant challenges to existing thermal management systems, and traditional cooling methods are not capable of meeting their heat dissipation needs. To enhance the heat dissipation efficiency of chip thermal management systems, a novel three-dimensional oscillating heat pipe (3D-OHP) with a flat structure at the bottom of the evaporation section was designed, which facilitates better contact with the heat source. Additionally, to further enhance the operational performance of the 3D-OHP, this work use chemical etching and self-assembly methods to alter the wettability of the internal surface of the 3D-OHP, examining its start-up and heat transfer performance under both vertical and horizontal installation conditions. The results indicate that regardless of vertical or horizontal installation, the 3D-OHP with super-hydrophilic/super-hydrophobic combination surfaces exhibit the best start-up and heat transfer performance. The start-up temperatures of the 3D-OHP are reduced by 22.29 % and 13.50 %, and the thermal conductivities are improved by 15.33 % and 62.45 % compared to the untreated 3D-OHP. Additionally, under the same heating power and wettability conditions, its performance in vertical installation is superior to that in horizontal installation, indicating that this heat pipe is more suitable for vertical installation. The above research provides valuable insights for scholars seeking to enhance the operational performance of 3D-OHPs by altering the wettability of the inner surface, thereby improving the heat dissipation efficiency of power chip thermal management systems. • 3D-OHP operating performance was studied for two installation conditions. • The effect of super-hydrophilic/super-hydrophobicity on 3D-OHP was studied. • The 3D-OHP performance under vertical installation was optimal. • Combination of super-hydrophilic/super-hydrophobic 3D-OHP performed best.