scispace - formally typeset
Search or ask a question
Author

Simon Otten

Bio: Simon Otten is an academic researcher from MESA+ Institute for Nanotechnology. The author has contributed to research in topics: Wetting & Drop (liquid). The author has an hindex of 1, co-authored 1 publications receiving 88 citations.

Papers
More filters
Journal ArticleDOI
TL;DR: The general physical conditions required for capturing sliding drops on an inclined plane that is equipped with electrically tunable wetting defects are determined and it is shown that electrically Tunable defects can be used to guide sliding drops along actively switchable tracks—with potential applications in microfluidics.
Abstract: Controlling the motion of drops on solid surfaces is crucial in many natural phenomena and technological processes including the collection and removal of rain drops, cleaning technology and heat exchangers Topographic and chemical heterogeneities on solid surfaces give rise to pinning forces that can capture and steer drops in desired directions Here we determine general physical conditions required for capturing sliding drops on an inclined plane that is equipped with electrically tunable wetting defects By mapping the drop dynamics on the one-dimensional motion of a point mass, we demonstrate that the trapping process is controlled by two dimensionless parameters, the trapping strength measured in units of the driving force and the ratio between a viscous and an inertial time scale Complementary experiments involving superhydrophobic surfaces with wetting defects demonstrate the general applicability of the concept Moreover, we show that electrically tunable defects can be used to guide sliding drops along actively switchable tracks—with potential applications in microfluidics

96 citations


Cited by
More filters
Journal ArticleDOI
TL;DR: In this article, a review of extreme wetting states of surfaces, their fabrication processes focusing on plasma processing technology, and their incorporation into devices and systems is presented, and perspectives and challenges are discussed.

170 citations

Journal ArticleDOI
TL;DR: A physical model is developed to estimate the energy dissipation by the defects and predict the transition from bouncing to sticking and macroscopic enhancements in spray retention and surface coverage for natural and synthetic non-wetting surfaces are demonstrated.
Abstract: Retention of agricultural sprays on plant surfaces is an important challenge. Bouncing of sprayed pesticide droplets from leaves is a major source of soil and groundwater pollution and pesticide overuse. Here we report a method to increase droplet deposition through in-situ formation of hydrophilic surface defects that can arrest droplets during impact. Defects are created by simultaneously spraying oppositely charged polyelectrolytes that induce surface precipitation when two droplets come into contact. Using high-speed imaging, we study the coupled dynamics of drop impact and surface precipitate formation. We develop a physical model to estimate the energy dissipation by the defects and predict the transition from bouncing to sticking. We demonstrate macroscopic enhancements in spray retention and surface coverage for natural and synthetic non-wetting surfaces and provide insights into designing effective agricultural sprays.

148 citations

Journal ArticleDOI
TL;DR: Electrowetting on liquid-infused film (EWOLF) as mentioned in this paper is a method for complete reversibility and controlled droplet oscillation suppression for fast optical imaging for optical imaging.
Abstract: Electrowetting on liquid-infused film (EWOLF): Complete reversibility and controlled droplet oscillation suppression for fast optical imaging

118 citations

Journal ArticleDOI
TL;DR: In this article, the authors present a class of active surfaces by stably impregnating active fluids such as ferrofluids into a textured surface, which can manipulate a variety of materials including diamagnetic, conductive and highly viscous fluids, and additionally solid particles.
Abstract: Droplet manipulation and mobility on non-wetting surfaces is of practical importance for diverse applications ranging from micro-fluidic devices, anti-icing, dropwise condensation, and biomedical devices. The use of active external fields has been explored via electric, acoustic, and vibrational, yet moving highly conductive and viscous fluids remains a challenge. Magnetic fields have been used for droplet manipulation; however, usually, the fluid is functionalized to be magnetic, and requires enormous fields of superconducting magnets when transitioning to diamagnetic materials such as water. Here we present a class of active surfaces by stably impregnating active fluids such as ferrofluids into a textured surface. Droplets on such ferrofluid-impregnated surfaces have extremely low hysteresis and high mobility such that they can be propelled by applying relatively low magnetic fields. Our surface is able to manipulate a variety of materials including diamagnetic, conductive and highly viscous fluids, and additionally solid particles.

108 citations

27 Oct 2014

104 citations