High Heat Flux Boiling Heat Transfer Through Nanoporous Membranes

Boiling heat transfer utilizes the latent heat of vaporization of a liquid to dissipate high heat flux and has been used for thermal management of high power electronic and optoelectronic devices. However, there are drawbacks in traditional boiling configurations: in pool boiling, the critical heat flux (CHF), typically no higher than 200 W/cm ² , is insufficient to meet the stringent demand of high power devices; flow boiling in microchannels could achieve higher heat flux, but are often accompanied with flow instabilities, causing temperature and pressure fluctuations that are detrimental to the device performance. Here, we demonstrate a new boiling heat transfer mechanism: thin film boiling on nanoporous membranes, in which the working principle is different from either the flow boiling or the pool boiling. We achieved a stable boiling regime with a high CHF close to 690 W/cm ² , which is significantly higher than that in pool boiling. Our study provides a new approach for achieving stable high heat flux boiling heat transfer.