A Dynamic and DE-wetting Process Introduced by Experts
April 21, 2008 By Parul Gupta
Would you prefer a kitchen surface that launders itself? With technological improvements like this could a single step closer after a discovery from Nottingham Trent University and Northumbria University.
Utilizing experimental methods, scientists have made the very first direct observation of the elusive DE wetting procedure, which occurs when a liquid layer retracts to create a bead-shaped drop. The accomplishment could now boost a novel line of study and result in breakthroughs involving the usage of liquids, like better layering and more efficient self-cleaning planes.
DE wetting is the reverse of 'spreading,' which is a common process that can be observed on a regular basis, like as when a drop of oil is placed on the pan surface. The liquid primarily has a bead-sort of shape, and it slowly extends to create a thin layer. The opposite process, known as DE wetting, occurs when a liquid layer retracts from a solid layer to create a bead-shaped drop that can be identified when a window is left to get dry.
Lecturer Glen McHale, the Pro-Vice Chancellor at Northumbria University and Lecturer of Material and Applied Physics, says "Our experimental set-up opens up the feasibility of preparing liquid shaped in a highly regulated manner, which then dewets. It can result in novel methods for liquid manipulation in technologies like self-cleaning and coating surfaces."
By incorporating very sleek patterned electrodes in the solid and cautiously organizing them into a circular structure, the group accomplished the formation of a sleek circular liquid layer. By shifting off the voltage, they disclosed, for the very first time, the complete DE wetting procedure of the liquid layer back to a bead-sort drop shape.
"Initially, one may have expected that DE wetting is only the reversal process of spreading. Surprisingly, we identified that DE wetting is not spreading in reverse," says Professor Carl Brown from Nottingham Trent University's School of Technology and Science. "Rather of a smooth pattern of drop-like shapes, the DE wetting layer creates a rim at its own corner, which retracts at regular speed for most of the DE wetting procedure."
For understanding such behaviour, the group utilized a combination of numerical and theory simulations to rationalize the studies. Dr. Rodrigo Ledesma – Augliar, from Northumbria, says, that "Both the movements and the theory support that the liquid might adopt the nearest local equilibrium shape it can possess during DE wetting. It explains the levelled rim shape that survives the best in the entire process." So undoubtedly, for the entire team, the experiment seems to be a mind-blowing experience that would be beneficial for carrying further studies.
Further added by Dr. Michael Newton from Nottingham Trent University, "Our technique can be utilized to learn more about the understated methods behind other types of DE wetting procedures like evaporation, condensation and droplet rebound. Such procedures are crucial for applications like fog-collection, lubrication, and coating. The method introduced can also be utilized for characterizing liquid features when just tiny volumes are available."