Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
The Challenges of Being Small
For juvenile fish, feeding is a challenge. Their small size — often less than 5 mm in length — makes hydrodynamically capturing prey much harder because of viscosity’s relatively larger effect on them. But size may not be the only factor in determining their success, as a new study shows. Researchers studied feeding behaviors of…
Searching For Solar Neutrinos
An experiment in Italy has reported new findings confirming a long-standing theory of nuclear fusion in our Sun. The researchers were able to detect neutrinos released by the relatively rare fusion of carbon and nitrogen. But catching those neutrinos took an impressive fluid dynamical feat. The Borexino solar-neutrino detector is essentially an enormous nylon balloon,…
When Shear Meets Slip
One of the classic concepts students learn early in their fluids education is the no-slip condition. In essence, this idea says that friction between a solid object — say, a wall — and the fluid immediately next to it is such that no movement is possible where they meet. The fluid cannot “slip” along the…
Alien Eggs? A Virus?
Nope, they’re hydrogel beads! The team at Chemical Bouillon seem to have once again coated them in something like paint before placing them in water. As the gel beads absorb water, they expand, tearing through their coating. The result is weirdly mesmerizing and kind of creepy. It’s no wonder that special effects artists have historically…
How Well Do Masks Work?
Many mixed messages have been spread about the efficacy of masks in preventing transmission of COVID-19. Nevertheless, there is good evidence that they help, as discussed in this video from It’s Okay to Be Smart. Much of the video shows schlieren imaging of a (healthy) individual engaging in regular activities – like talking, breathing, and…
Shake It!
Vibrate a pool of water, and you’ll get Faraday waves, ripple-like excitations that form their own distinctive pattern compared to the driving vibration. But you don’t have to vibrate a pure liquid to see Faraday waves. A recent study observed them in vibrated earthworms! Odd as this may sound, the results make sense. When anesthetized…
Leaping Hoops
Some water-walking insects are able to leap off a watery interface. One way to model these creatures is with elastic hoops, which can also propel themselves off the water’s surface. In this video, researchers explore some of the factors that affect the jump, like hoop geometry, material, and hydrophobic coatings. Wider hoops jump better than…
Ejecting Water from a Smartwatch
Making electronics water-resistant can be a challenge, but as this Slow Mo Guys video demonstrates, engineers have some clever ways to deal with unwanted liquids. The Apple Watch, for example, uses its speakers to eject water that gets into the watch during immersion. As seen above, the vibration of the speakers ejects most of the…
Branching Sparks from Senko-hanabi
Senko-hanabi are a Japanese firework, somewhat similar to a sparkler. But instead of being driven by burning powder, the senko-hanabi’s sparks come from bursting liquid droplets undergoing an exothermic reaction with air. Chemistry aside, the effect is similar to what goes on in soda water. As bubbles within the liquid nucleate and move to the…
Internal Waves in the Andaman Sea
Differences in temperature and salinity create distinct layers within the ocean. When combined with flow over submerged topography — underwater canyons, mountains, and reefs — it makes waves. But those waves aren’t always apparent when sitting at the surface. Instead, they travel along those ocean layers as internal waves that can be as tall as…