Abstract
Subcooled flow boiling of water is performed in a horizontal small rectangular channel with 5mm height and 14mm width for the purpose of high heat flux cooling of power electronics. A small heating surface of 10mm length or 20mm length for 10mm width is located on the bottom surface of the channel. Microbubble Emission Boiling, MEB, occurs in transition boiling and higher heat fluxes than 500W/cm^2 are obtained. For the longer heating surface, the heat flux in MEB decreases for the down stream of the heating surface because of falling the subcooling of liquid. At lower liquid subcooling of 20K and lower liquid velocity of 0.3m/s, unstable MEB is observed to transit easily to film boiling. The experimental results suggest how to keep the subcooling of liquid at least 20K for the down stream section of electronic devices.
