The Effect of a Honey-Comb Porous Plate on the Critical Heat Flux Under Reduced Pressure Conditions

Enhancement of pool boiling heat transfer using a honeycomb porous plate (HPP) under atmosphere pressure has been experimentally examined. The previous research found that the critical heat flux (CHF) could be enhanced by up to three times above that of a plain surface. Considering the operating temperature in microelectronic devices, boiling at sub-atmospheric pressures for maintaining the lower surface temperature while removing high heat flux is required. Under circumstances of low pressure, there is a scarcity of research about boiling heat transfer for porous materials. Liquid supply is promoted by capillary action and vapor escape is facilitated by separating liquid flow channels from vapor flow channels in the HPP, and the CHF was expected to be improved even at reduced pressure conditions. Therefore, the CHF in saturated water boiling through an HPP at low pressure was studied in the current research. A more generalized understanding of the system pressure and the enhancement effect was provided, which made it possible to mitigate the enhancement technology bottlenecks through electronic devices and looked upon as further elaboration of the boiling heat transfer mechanism on honey-comb porous surfaces. There were three different pressures (51 kPa, 76 kPa and 100 kPa) investigated on the HPP; the results on the plain surface under the identical operating conditions were the same for each of the three pressures tested on the HPP.