Abstract
Atmospheric water is emerging as an important potable water source. The present work experimentally and theoretically investigates water condensation and collection on flat surfaces with contrasting contact angles and contact angle hysteresis (CAH) to elucidate their roles on water mass collection efficiency. The experimental results indicate that a hydrophilic surface promotes nucleation and individual droplets growth, and a surface with a low CAH tends to let a smaller droplet to slide down, but the overall water mass collection efficiency is independent of both surface contact angle and CAH. The experimental results agree well with our theoretical calculations. During water condensation, a balance has to be struck between single droplet growth and droplet density on a surface so as to maintain a constant water droplet surface coverage ratio, which renders the role of both surface wettability and hysteresis insignificant to the ultimate water mass collection. Moreover, water droplets on the edges of a surface grow much faster than those on the non‐edge areas and thus dominate the contribution to the water mass collection by the entire surface, directly pointing out the very important role of edge effect on water condensation and collection.
Highlights
In a typical water condensation, there are three sequential steps: nucleation, present work experimentally and theoretically investigates water condengrowth of individual water droplet, and sation and collection on flat surfaces with contrasting contact angles and contact angle hysteresis (CAH) to elucidate their roles on water mass collection efficiency
A balance has to be struck between single droplet growth and droplet density on a surface so as to maintain a constant water droplet surface coverage ratio, which renders the role of both surface wettability with a temperature lower than vapor saturation temperature
A good understanding of water condensation, a phase change of droplet size on flat surfaces and constant water droplet surprocess in which water vapor is transformed to liquid water face coverage ratio, which is defined as ratio of the projected and which involves both heat and mass transfers, is a key to an area of the droplets to the total substrate surface area.[2a,4] Both effective atmospheric water harvesting
Summary
In a typical water condensation, there are three sequential steps: nucleation, present work experimentally and theoretically investigates water condengrowth of individual water droplet, and sation and collection on flat surfaces with contrasting contact angles and contact angle hysteresis (CAH) to elucidate their roles on water mass collection efficiency. Heterogeneous nucleation is a dominant mechanism in forming atmospheric water liquid under ambient conditions, and it is affected by parameters and hysteresis insignificant to the ultimate water mass collection Such as substrate temperature, vapor preswater droplets on the edges of a surface grow much faster than those on the non-edge areas and dominate the contribution to the water mass collection by the entire surface, directly pointing out the very important role of edge effect on water condensation and collection. When the state of substrate and vapor is set, water vapor nucleates faster on a hydrophilic substrate than on a hydrophobic one due to its lower energy barrier.[3] Following the nucleation is growth of an individual water droplet, 1 Introduction and in this step, water vapor condenses on the preformed droplet surfaces and the mass of individual liquid droplet grows. A good understanding of water condensation, a phase change of droplet size on flat surfaces and constant water droplet surprocess in which water vapor is transformed to liquid water face coverage ratio, which is defined as ratio of the projected and which involves both heat and mass transfers, is a key to an area of the droplets to the total substrate surface area.[2a,4] Both effective atmospheric water harvesting
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
