Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Ice Discs Surf on Herringbones
Inspired by the roaming rocks of Death Valley, researchers went looking for ways to make ice discs self-propel. Leidenfrost droplets can self-propel on herringbone-etched surfaces, so the team used them here, as well. On hydrophilic herringbones, they found that meltwater from the ice disc would fill the channels and drag the ice along with it.…
Albuquerque: Balloonist Paradise
Albuquerque, New Mexico’s unique weather characteristics make it a popular destination for hot-air balloonists. While balloonists can control their altitude by warming or venting the air in their balloon, their horizontal travel comes at the mercy of the wind. (Just ask the erstwhile Wizard of Oz.) What makes Albuquerque special is a combination of topography,…
Flipping Icebergs
When an iceberg flips, it creates waves that can endanger ships nearby, but the move can also trigger further melting. In the ocean, many factors, including wind and waves, can contribute to an iceberg flipping, so researchers studied small, lab-scale versions to see how melting–alone–affects an iceberg’s likelihood of flipping. The results showed that melting…
Spinning Water
If you spin a tank of water at a constant speed, it takes on a curved, parabolic shape–a demonstration often called Newton’s bucket. Here, a team from UCLA shows how it’s done, both in terms of the equipment needed and a concise explanation of the physics. In the rotating experiment, water is subjected to both…
“Veins of Light and Rivers of Fog”
Tendrils of fog flow over the crest of a hill in this award-winning photograph from Ray Cao. Seen in timelapse, scenes like this show the sloshing, wave-like motion of fog. They’re a beautiful reminder that air and water move much the same. (Image credit: R. Cao/IAPOTY; via Colossal)
Striations on the Sun
One of the perpetual challenges for fluid dynamicists is the large range of scales we often have to consider. For something like a cloud, that means tracking not only the kilometer-size scale of the cloud, but the large eddies that are about 100 meters across and smaller ones all the way down to the scale…
Dispersing Pollutants via Smokestack
In our industrialized society, pollutants are, to an extent, unavoidable. Even with technologies to drastically reduce the amount of pollutants leaving a factory or plant, some will still get released. It’s up to engineers to make sure that those released spread out enough that their overall concentration does not pose a risk to public health.…
Dusty Clouds Make More Ice
Even when colder than its freezing point, water droplets have trouble freezing–unless there’s an impurity like dust that they can cling to. It’s been long understood in the lab that adding dust allows water to freeze at warmer temperatures, but proving that at atmospheric scales has been harder. But a new analysis of decades’ worth…
A Braided River
The Yarlung Zangbo River winds through Tibet as the world’s highest-altitude major river. Parts of it cut through a canyon deeper than 6,000 meters (three times the depth of the Grand Canyon). And other parts, like this section, are braided, with waterways that shift rapidly from season to season. The swift changes in a braided…
Smoke Bomb
With a flurry of motion along its pectoral fin, a sting ray lifts the sand nearby and disappears into the turbid cloud. This tactic helps the animal both hide and escape. In a similar move, sting rays and other bottom-dwelling fish can bury themselves in sand.(Image credit: Y. Coll/OPOTY; via Colossal)