Numerical Analysis and Experimental Study on Immersive Heat Sinks with Copper Foam

Abstract

To deal with the heat transfer problem of CPU with high heat flux, porous metal structure combined with immersion cooling technology is one of the promising solutions. In this work, two types of immersive heat sink made of copper foam were proposed, i.e., groove-type heat sink and laminated-type structure heat sink. Novec7100 is used as a working fluid. Multi-scale simulation is applied to establish geometric model of porous medium. The COMSOL is used for the fluid-structure coupling heat transfer module to conduct a macro CFD analysis of the heat sink. The micro and macro effects of heat transfer of the two types of heat sinks are compared, and vital microscopic parameters and structural parameters are proposed to maximize the heat dissipation efficiency and save the space. The simulation results indicate that the better solution is the laminated type heat sink which can control CPU chip temperature below 110°C at 500W without pump drive. To further improve the heat dissipation effect, a pump drive is proposed in the system. The simulation and experiment results show that when inlet velocity reaches 0.03m/s, the system with pump drive can achieve the best heat dissipation effect. The CPU chip at 500W heating power can be cooled down to 65.86°C (experimental data) or 67.1°C（simulation data）

Keywords: Immersive heatsink, Porous medium, boiling；Multi-scale simulation, NOVEC 7100