At a lotus leaf, drops simply roll off, but a concrete wall is wetted by them. The reason for this lies in the condition of the surface. Tiny structures are the reason for drops not to adhere to the surface. Researchers at the Technische Universität Kaiserslautern (TUK) are investigating this effect using a 3D high-speed camera system. This helps them to see what happens when drops hit difference surfaces. The findings could help to reduce machine wear and tear or to keep plants free of contamination.
During the Achema, a trade fair for the process industries in Frankfurt, they are presenting this technology at the research stand of the federal state Rhineland-Palatinate from June 11-15 (hall 9.2, stand A86a).
If drops of water fall on a lotus leaf, they simply roll off. This phenomenon, also known as "lotus effect", is based on the fact that the surface of those leafs shows unevenness (nubs) which in the end makes the drop roll off. The tiny structures were discovered by the botanist Wilhelm Barthlott in the 1970s thanks to a scanning electron microscope. The very same principle is now used for window glass or wall paint.
Researchers of the Department Mechanical and Process Engineering at the TU Kaiserslautern engage in this this phenomenon. They investigate the behavior of drops when they encounter surfaces which provide differently formed micro structures, such as nubs, grid or trapezoid.
"Here we deal with structures that are significantly smaller than the diameter of a hair, for example," says Fabian Krull, who investigates this topic within the scope of his doctorate at the Department of Particle Process Engineering of Professor Dr. Sergiy Antonyuk. They are in a range of 100 nanometer and 10 micrometer; dimensions not visible to the human eye. And still those structures can influence the impingement of drops on a surface in different ways.
In order to be able to observe this process in detail, three high-performance cameras are used. "They take pictures from different angles", says Fabian Krull. Software is used to then convert the data to a 3D picture. "That way we can observe step by step what happens when a drop hits different surfaces", explains Professor Antonyuk. Furthermore, the engineers simulate the fall of those drops with their computer models.
Research is carried out within the framework of the Collaborative Research Centre 926 "Component Surfaces: Morphology on a microscale", which is subsidized by the German Research Foundation. The researchers' findings might be able to help reduce friction of machines or design surfaces of industrial plants to prevent dust and contamination particles to accumulate on the machines. This would also be useful for hospitals so that microorganisms cannot adhere to certain things.
The engineers are presenting their camera system and research work at the Achema.
Questions can be directed to:
Prof. Sergiy Antonyuk
Phone: +49 (0) 631 205-3524
Klaus Dosch, Department of Technology and Innovation, is organizing the presentation of the researchers of the TU Kaiserslautern at the fair. He is the contact partner for companies and, among other things, establishes contacts to science.
Contact: Klaus Dosch, Email: dosch[at]rti.uni-kl.de, Phone (also during the fair): +49 (0) 631 205-3001
Melanie Löw | Technische Universität Kaiserslautern
Fingerprint spectroscopy within a millisecond
24.06.2019 | Fraunhofer-Institut für Angewandte Festkörperphysik IAF
Release agent-free: ReleasePLAS® technology replaces silicone coating in wax injection molding
21.06.2019 | Fraunhofer IFAM
From June 25th to 27th 2019, the Fraunhofer Institute for Digital Media Technology IDMT in Ilmenau (Germany) will be presenting a new solution for acoustic quality inspection allowing contact-free, non-destructive testing of manufactured parts and components. The method which has reached Technology Readiness Level 6 already, is currently being successfully tested in practical use together with a number of industrial partners.
Reducing machine downtime, manufacturing defects, and excessive scrap
The quality of additively manufactured components depends not only on the manufacturing process, but also on the inline process control. The process control ensures a reliable coating process because it detects deviations from the target geometry immediately. At LASER World of PHOTONICS 2019, the Fraunhofer Institute for Laser Technology ILT will be demonstrating how well bi-directional sensor technology can already be used for Laser Material Deposition (LMD) in combination with commercial optics at booth A2.431.
Fraunhofer ILT has been developing optical sensor technology specifically for production measurement technology for around 10 years. In particular, its »bd-1«...
The well-known representation of chemical elements is just one example of how objects can be arranged and classified
The periodic table of elements that most chemistry books depict is only one special case. This tabular overview of the chemical elements, which goes back to...
Light can be used not only to measure materials’ properties, but also to change them. Especially interesting are those cases in which the function of a material can be modified, such as its ability to conduct electricity or to store information in its magnetic state. A team led by Andrea Cavalleri from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg used terahertz frequency light pulses to transform a non-ferroelectric material into a ferroelectric one.
Ferroelectricity is a state in which the constituent lattice “looks” in one specific direction, forming a macroscopic electrical polarisation. The ability to...
Researchers at TU Graz calculate the most accurate gravity field determination of the Earth using 1.16 billion satellite measurements. This yields valuable knowledge for climate research.
The Earth’s gravity fluctuates from place to place. Geodesists use this phenomenon to observe geodynamic and climatological processes. Using...
24.06.2019 | Event News
29.04.2019 | Event News
17.04.2019 | Event News
25.06.2019 | Power and Electrical Engineering
25.06.2019 | Studies and Analyses
25.06.2019 | Health and Medicine