Numerical Investigation on Heat Transfer Performance of a Single-Phase Immersion Cooling System

The current trend of miniaturization, integration and high density of electronic devices drives up the heat flow density of data centers, resulting in the traditional air-cooled cooling mode approaching its theoretical heat transfer limit. Immersion cooling method has a great potential to cool electronic devices by submerging them into thermally conductive dielectric liquids. In this study, efforts are focused on single-phase immersion cooling and a numerical model of PCB-level immersion cooling tank is constructed. Three mainboards are arrayed and submerged in a dielectric fluid (FC40). Each mainboard has four CPUs that provide the heat power. The straight-finned heat sink is attached on each CPU surface. The effects of the different heat loads, the multi-PCB arrangements, the inlet-outlet locations of the flowing liquid and the variation of inlet temperature on the heat transfer performance are analyzed through the temperature of the CPU and thermal resistance of this immersion cooling system.