Chinese Researchers Make Falling Liquid Droplets Swirl And Twirl Like Ballerinas

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Falling liquid droplets usually splash or flatten out upon hitting a surface (Credit : Skeezy/Pixabay/CCO)

When a falling liquid droplet hits a surface, like a raindrop hitting pavement, it either flattens and spreads out evenly, or produces a sharp-edged splash. Now, a team of Chinese researchers has created a surface which allows the descending liquid to rebound and swirl around like a graceful dancer.

The team, led by Huizeng Li of the Chinese Academy of Sciences, Beijing (CAS), began by coating an aluminum surface with nonstick material, like the kind used on cooking utensils. The researchers then created several designs by covering portions of the nonadhesive area so that it would act like a normal, "wettable" surface – meaning it would cause the falling droplets to spread around. An ultraviolet (UV) light shone over the entire surface completed the setup.

Scientists made the water droplets dance by creating patterns of low and high adhesive areas (Credit: Nature.com)

When a water droplet hit the patterned surface, the part of it that hit the wettable areas stayed on the surface, while the portions that came in contact with the waterproof areas sprang up back in the air. According to the researchers, who published their study in the journal Nature on March 5, 2019, this created a set of unbalanced forces that pulled unevenly at the water droplet - more in some parts than in others - and caused it to "dance"

By varying the designs of the wettable and water-repellant areas, the researchers were able to control the motion of the droplet and make it roll, twirl and even perform a combination of different actions. While the dancing water is certainly mesmerizing to watch, controlling how liquid leaps off a surface may also have some practical applications – like creating self-cleaning surfaces or mixing different materials.

Resources: nature.com, Sciencemag.org

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436 Comments
  • octopus1234
    octopus1234Friday, May 8, 2020 at 7:32 am
    It twirls! So cool!
    • animereina2020
      animereina2020Thursday, May 7, 2020 at 7:40 pm
      Isn't it satisfying how the water spins?
      • animereina2020
        animereina2020Thursday, May 7, 2020 at 7:39 pm
        It spins and jumps in the air! Science....science.....SCIENCE 😝
        • animereina2020
          animereina2020Thursday, May 7, 2020 at 7:38 pm
          Omg! I saw a video like this before!
          • galaxy_fox12
            galaxy_fox12Tuesday, March 24, 2020 at 3:55 pm
            Seeing it twirl and swirl makes me wanna 💃DANCE💃
            • galaxy_fox12
              galaxy_fox12Tuesday, March 24, 2020 at 3:54 pm
              Inpressive 👍
              • lpsbrooklyn11
                lpsbrooklyn11Tuesday, March 24, 2020 at 12:20 pm
                That's so cool
                • Ca vaWednesday, October 16, 2019 at 7:53 am
                  So cool Iwonder if they could use sound waves
                  • aiahsfm_sl
                    aiahsfm_slThursday, October 3, 2019 at 9:21 am
                    It was so satisfying
                    • aiahsfm_sl
                      aiahsfm_slThursday, October 3, 2019 at 9:21 am
                      Wow that was EPIC