Fig xA Droplet wetting phenomena in different states of microstructured

Additionally, in view of NBHT, the onset of nucleate boiling (ONB), single bubble growth, bubble coalescence, and mushroom bubble generation, which AS-604850 key mechanisms of boiling, should be quantitatively studied. The physical definitions and reasonable explanations for CHF and its triggering mechanism also have to be understood. From the ONB, the surface condition would strongly influence the entire boiling regime (single bubble growth, bubble coalescence, and mushroom bubble generation), finally CHF. However, the recent reports of CHF enhancement provided the reduced Rayleigh–Taylor instability wavelength at film boiling condition [25] and [26]. As previously described in Section 3 and 4, the bubble behavior such as nucleation, growth, and departure was basically induced by the phase change phenomena from liquid to vapor. Thus, the wet liquid on the heater surface would be an important parameter to explain the NBHT and CHF mechanism according to the surface condition. On the other hand, even though the liquid cannot contact on the heater surface in film boiling such as quenching experiment, the pool boiling curve from quenching of the micro/nano structured surfaces shows the enhancement of CHF and minimum heat flux point. In addition, the Leidenfrost point on the micro/nano structured surfaces is also higher than colonial on bare surface [138]. Here, we raised interesting questions as follows.•If the surface condition would influence the entire boiling regime from ONB to CHF by means of liquid wetting, how the surface condition in film boiling leads the reduced Rayleigh–Taylor instability wavelength?•In quenching process from film boiling to nucleate boiling, the boiling curve shows the enhancement of CHF and minimum heat flux point. At the early state of quenching (film boiling), how the vapor film feels the nano/microstructures without any liquid contact to a surface?•Based on above questions, could the surface condition influence on the entire boiling regime understand beyond the CHF?