Passive Two Phase Cooling Using Super-hydrophilic Surface and Volatile Working Fluid for Electronic Devices

Abstract

With rapid development of electronic devices, their internal heat generation become significantly denser. Accordingly, the thermal management becomes increasingly important for the stable operation. For the heat dissipation performance improvement in limited installation spaces, passive two-phase cooling technique using water is being applied. Instead of water, using refrigerants as the working fluid is advantageous in many aspects. In this study, a gravity-driven cooling circuit using R134a, R1234ze(Z) and R1234ze(E) is experimentally investigated. The experimental circuit successfully kept the heating temperature simulating electronic devices below 80 °C at heat fluxes up to 111 Wcm^-2 and 125 Wcm^-2 with R1234ze(Z) and R1234ze(E), respectively. By using a super-hydrophilic boiling surface, the heat flux was extended to 133 and 135 W cm^-2 in R1234ze(Z) and R1234ze(E). The experiment demonstrated that using the refrigerant and super-hydrophilic surfaces could be a beneficial solution for electronic device cooling.