Surface enhancement for boiling heat transfer through micro holes for electronic cooling applications

This work reports the nucleate boiling heat transfer characteristics of n-pentane on smooth and enhanced surfaces. Surface modifications were carried out on stainless steel surfaces by fabricating microholes of diameter between 0.3 and 0.7 mm arrays using electric discharge machining. Pool boiling experiments were carried out at normal atmospheric pressure. Experiments have been performed for applied effective heat flux range between 1 and 10 W cm−2. An enhancement of 20–45% in heat transfer coefficient was observed on the enhanced surface compared to the smooth surface. The heat transfer improvement in the enhanced surface can be attributed to more active nucleation sites, better rewetting phenomenon, and favorable bubble growth and release mechanism. Further changing the material from steel to brass enhances the heat transfer coefficient by 20%. This will be a viable option as a cooling technology for high-power electronic industries.