Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Crystalline Critters
In 5th grade, I grew crystals by evaporating solutions of salt water from miniature pie tins. The results were white, boxy crystals whose size depended on how much salt I’d managed to dissolve into the water. But it turns out I could have gotten much cooler results if I’d evaporated my salt water a drop…
Slow Mo Espresso
High-speed photography gives us an alternate glimpse of reality. Here it provides an all-new perspective on making espresso. Surface tension plays a starring role, first in pulling together the film that forms over the exit, then in creating the drips and drops that follow. The break-up of espresso into individual droplets is an example of…
Fungal Fluid Dynamics
Many plants gain the soil-bound nutrients they need by trading with symbiotic fungi. Underground, these fungi spread networks that gather and store phosphorus, which they then trade with host plants to get the carbon they need. Research shows that the fungi can be shrewd traders, moving phosphorus from nutrient-rich areas to poorer ones in order…
Sediment and Coral
As rivers wash sediment toward the sea, they carve elaborate deltas like that of the Rio Cauto in Cuba. Over time these sediments build up marshes, swamps, lagoons, and other wetlands that provide critical habitat and flood control. Sediment also washes into the bay, where it interacts with the coral reefs (light green lines on…
Molten Thermite
This glowing, molten liquid captured by the Slow Mo Guys is thermite. The chemical reaction behind thermite is highly exothermic, hence its intense glow. There’s some great fluid dynamics hiding in this video. First, there’s the dripping thermite (Image 1), which breaks up into droplets via the Plateau-Rayleigh instability before shattering when it hits the…
Droplets From Jets
On the ocean, countless crashing waves are creating bubbles. When they burst, those bubbles generate jets and droplets that spray into the sky, carrying sea salt, dust, and biological material into the atmosphere. Researchers know these droplets and their evaporation are important for understanding environmental processes, but figuring out how to capture that importance in…
“Vorticity 3”
Mike Olbinski’s “Vorticity 3” is a stunning view of storm chasing in the American West. I’ve learned after years in Colorado to always look up because dramatic skies are common here, as is seeing rain falling miles away. Olbinski’s film captures all of that grandeur and more, giving all of us a glimpse inside the…
The Power of a Penguin’s Rectum
When brooding their eggs, penguins can rarely leave the nest, but answering nature’s call is still necessary. To keep the nest clean, Adélie penguins project their feces up to more than a meter away. A new study refines previous calculations on this subject and finds that the penguin’s rectum develops far higher pressures than that…
The Explosive Vaporization Derby
When pressurized, liquids can be superheated to temperatures well above their normal boiling point. When the pressure is released, the liquid will start boiling, sometimes explosively. In this video, researchers explore that dynamic by “racing” a series of liquids against one another. Each racer has been heated to a different temperature beyond the expected boiling…
Artificial Microswimmers
Tiny organisms swim through a world much more viscous than ours. To do so, they swim asymmetrically, often using wave-like motions of tiny, hair-like cilia along their bodies. Mimicking this behavior in artificial swimmers is tough; how would you actuate so many micro-appendages? A new study offers a different method: inducing cilia-like waves using magnetic…