Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
“It’s All About Flow”
Fluid dynamicists, like other scientists, have lives and interests well beyond our research. Ivo Nedyalkov, for example, is a professional rapper in addition to a PhD-level fluid dynamicist. In “It’s All About Flow,” Dr. Ivo brings those areas of expertise together with a rap all about fluid dynamics. The version embedded here is a bit…
A Microfluidic Zoo
Microfluidic channels are excellent at creating a steady supply of droplets. But depending on the characteristics of the two viscous fluids being used, as well as factors like flow rate and channel geometry, the results can be anything from well-defined and separated drops to steady jets to wild instabilities. The image above shows a series…
To Beat Surface Tension, Tadpoles Make Bubbles
For tiny creatures, surface tension is a formidable barrier. Newborn tadpoles are much too small and weak to breach the air-water surface in order to breathe. Researchers found that, instead, the 3 millimeter creatures place their mouths against the surface, expand their mouth to generate suction, and swallow a bubble consisting largely of fresh air.…
Surface Jets in Coalescing Droplets
What goes on when droplets merge is tough to observe, even with a high-speed camera. There are many factors at play: any momentum in the droplets, surface tension, gravity, and Marangoni forces, to name a few. A new study that simultaneously records multiple views of coalescence is shedding some light on these dynamics. The results…
Paint Versus Hydrogel
In this bizarre short film, we get to see a battle between dissolution and absorption. I think the Chemical Bouillon team has coated hydrogel beads in a layer of paint and then immersed them in water. As the beads absorb water, they expand and grow, tearing their fragile outer layer of paint to smithereens. One…
Using Electric Fields to Avoid Dripping
Anyone who’s painted a room at home is familiar with the frustration of drips. At certain inclinations, practically every viscous liquid develops these gravity-driven instabilities. They’re troublesome in manufacturing as well, where viscous films are often used to coat components and unexpected drips can ruin the process. To avoid this, researchers are adding electric fields…
Ice Patterns
Periods of freezing and thawing can leave complicated patterns in ice, as seen in this aerial photo of Binnewater Lake in New York. Ice rarely forms evenly on large bodies like this, so there are always underlying weaknesses. A hard freeze may have caused the ice to contract, forming the initial radial pattern. Then warmer…
Inferring Flows with Neural Networks
Fluid dynamicists have long used flow visualization methods to get a qualitative sense for flows, but it’s rare to derive much quantitative data from this imagery. But that may soon change thanks to a new computational technique, called Hidden Fluid Mechanics, that uses data from flow visualizations combined with physics-informed neural networks to derive the…
Boiling Water Using Ice Water
Steve Mould demonstrates a neat thermodynamic trick in this video by using ice water to boil hot water. The key to understanding this is recognizing that the boiling point of water depends both on its temperature and its pressure. Here’s the set-up (which, to be clear, neither he nor I recommend you try yourself): microwave…
Gliding Birds Get Extra Lift From Their Tails
Gorgeous new research highlights some of the differences between fixed-wing flight and birds. Researchers trained a barn owl, tawny owl, and goshawk to glide through a cloud of helium-filled bubbles illuminated by a light sheet. By tracking bubbles’ movement after the birds’ passage, researchers could reconstruct the wake of these flyers. As you can see…