Demonstration of super-cooling technology with nanoparticles--assembled bi-porous structure and its control

为了开发一种新型沸腾传热冷却装置，重点研究了纳米粒子组装双孔结构在受热面上的可行性。这种独特的多孔层既具有高透气性的微/微孔结构，又具有更强的毛细效应和高润湿性的纳米级孔结构。结果表明，即使在Leidenfrost条件下，水滴在具有纳米颗粒双孔层的高温壁上也会发生剧烈的沸腾和蒸发。此外，在高温和低温条件下，液滴的寿命都急剧缩短，这证明纳米颗粒组装的双孔层可以提高核沸腾状态下的传热速率和临界热流密度。

Feasibility of nanoparticles-assembled bi-porous structure on a heating surface is focused on in order to develop a new boiling heat transfer cooling device. This unique porous layer has both a micro/mini-pore structure with high permeability for discharging vapor and nano scale pore structure with a much stronger capillary effect as well as high wettability. It was confirmed that a water droplet intensely boiled and evaporated on a high temperature wall with the nanoparticles bi-porous layer even under Leidenfrost conditions. In addition, the life time of the droplet drastically decreases both in a high temperature and low temperature regimes, which proves that the nanoparticles-assembled bi-porous layer can enhance both heat transfer rate in a nucleate boiling regime and critical heat flux.