Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Professors' super waterproof surfaces cause water to bounce like a ball

21.05.2014

Research on super-hydrophobic surfaces could result in cleaner, more efficient power

In a basement lab on BYU’s campus, mechanical engineering professor Julie Crockett analyzes water as it bounces like a ball and rolls down a ramp.


A droplet of water beads up on top of a hydrophobic surface. Water beads up even more on super-hydrophobic surfaces

This phenomenon occurs because Crockett and her colleague Dan Maynes have created a sloped channel that is super-hydrophobic, or a surface that is extremely difficult to wet. In layman’s terms, it’s the most extreme form of water proof.

Engineers like Crockett and Maynes have spent decades studying super-hydrophobic surfaces because of the plethora of real-life applications. And while some of this research has resulted in commercial products that keep shoes dry or prevent oil from building up on bolts, the duo of BYU professors are uncovering characteristics aimed at large-scale solutions for society.

Their recent study on the subject, published in academic journal Physics of Fluids, finds surfaces with a pattern of microscopic ridges or posts, combined with a hydrophobic coating, produces an even higher level of water resistance--depending on how the water hits the surface.

“Our research is geared toward helping to create the ideal super-hydrophobic surface,” Crockett said. “By characterizing the specific properties of these different surfaces, we can better pinpoint which types of surfaces are most advantageous for each application.”

Their work is critical because the growing list of applications for super-hydrophobic surfaces is extremely diverse:

  • Solar panels that don’t get dirty or can self-clean when water rolls off of them
  • Showers, tubs or toilets you don’t want hard water spots to mark
  • Bio-medical devices, such as the interior of tubes or syringes that deliver fluids to patients
  • Hulls of ships, exterior of torpedoes or submarines
  • Airplane wings that will resist wingtip icing in cold humid conditions

But where Crockett and Maynes’ research is really headed is toward cleaner and more efficient energy generation. Nearly every power plant across the country creates energy by burning coal or natural gas to create steam that expands and rotates a turbine. Once that has happened, the steam needs to be condensed back into a liquid state to be cycled back through.

If power plant condensers can be built with optimal super-hydrophobic surfaces, that process can be sped up in significant ways, saving time and lowering costs to generate power.

“If you have these surfaces, the fluid isn’t attracted to the condenser wall, and as soon as the steam starts condensing to a liquid, it just rolls right off,” Crockett said. “And so you can very, very quickly and efficiently condense a lot of gas.”

The super-hydrophobic surfaces the researchers are testing in the lab fall into one of two categories: surfaces with micro posts or surfaces with ribs and cavities one tenth the size of a human hair. (See images of each to the right.)

To create these micro-structured surfaces, the professors use a process similar to photo film development that etches patterns onto CD-sized wafers. The researchers then add a thin water-resistant film to the surfaces, such as Teflon, and use ultra-high-speed cameras to document the way water interacts when dropped, jetted or boiled on them.

They’re finding slight alterations in the width of the ribs and cavities, or the angles of the rib walls are significantly changing the water responses. All of this examination is providing a clearer picture of why super-hydrophobic surfaces do what they do.

“People know about these surfaces, but why they cause droplets or jets to behave the way they do is not particularly well known,” Crockett said. “If you don’t know why the phenomena are occurring, it may or may not actually be beneficial to you.”

Todd Hollingshead | Eurek Alert!
Further information:
http://news.byu.edu/archive14-may-superhydrophobic.aspx

Further reports about: alterations bounce cameras coating microscopic properties steam surfaces tubes

More articles from Physics and Astronomy:

nachricht SF State astronomer searches for signs of life on Wolf 1061 exoplanet
20.01.2017 | San Francisco State University

nachricht Molecule flash mob
19.01.2017 | Technische Universität Wien

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>