HIGH HEAT FLUX PHASE CHANGE HEAT TRANSFER THROUGH NANOPOROUS MEMBRANES
Liquid-vapor phase change heat transfer has been intensively studied for thermal management of high power electronic and optoelectronic devices. Significant efforts have been made to enhance heat flux in phase change heat transfer, for both boiling and evaporation, with various types of micro and nanostructures. Nanoporous membranes have been proposed and theoretically shown as a promising candidate for high heat flux phase change heat transfer. However, the experimentally demonstrated heat flux over a device-relevant area (~cm2) has so far been lower than 50 W/cm2, which has cast doubt on the feasibility of achieving a high heat flux from nanoporous membranes. Here we carried out phase change heat transfer experiments using isopropyl alcohol (IPA) through anodized aluminum oxide (AAO) membranes. For membranes with a 200 nm nominal pore size on a 0.5 cm2 size area, we demonstrated a high heat flux of 210 W/cm2. The demonstration of high heat flux phase change heat transfer through nanoporous membranes on a device-scale area (~0.5 cm2) is significant for the thermal management for high power devices.