Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
“Arctic Fox in Blizzard”
A blue arctic fox bears the wind and snow of a Norwegian blizzard in this image by photographer Klaus Hellmich. The wind is strong enough to move snowflakes several centimeters in the time the camera’s shutter is open. This leaves the image full of streaklines that reveal the paths taken by the wind and snow.…
Richtmyer-Meshkov Instability
If you send a shock wave through a magnetized plasma–something that happens in both supernova explosions and inertial confinement fusion–it can trigger an instability known as the Richtmyer-Meshkov instability. The image above shows a form of this, taken from a simulation. Rather than treating the plasma as a single idealized fluid, the researchers represented it…
Testing Structures Against Hurricane Storm Surge
When hurricanes hit coasts, they bring with them incredible storm surge, which puts buildings right in the middle of ocean waves. To understand how to better protect against those conditions, engineers use facilities like the Directional Wave Basin to create smaller-scale versions of hurricanes. In this Practical Engineering video, Grady visited during a test that…
Improving Turbulence Models
Calculating turbulent flows like those found in the ocean and atmosphere is extremely expensive computationally. That’s why forecasting models use techniques like Large Eddy Simulation (LES), where large physical scales are calculated according to the governing physical equations while smaller scales are approximated with mathematical models. Researchers are always looking for ways to improve these…
Drag Reduction Via Bubbles
To help reduce greenhouse emissions, businesses are exploring systems that reduce a container ship’s drag by releasing bubbles beneath them. But how do bubbles reduce drag? To find out, researchers simulated a bubbly flow that mimics the underside of a moving ship. By playing with the balance between inertial forces, buoyancy, and surface tension, they…
“Crystal Garden – Seasons”
In this latest project, the Beauty of Science team explores colorful crystallization as chemicals precipitate out of evaporating solutions. The variety of shapes and colors is incredible. To see many more of these crystalline “gardens,” check out the video below and the project’s webpage. (Video and image credit: W. Zhu/Beauty of Science; via Colossal)
Mimicking Quantum Effects
Over the last 15 years or so, researchers have been exploring pilot-wave theory–originally proposed by De Broglie in the 1920s as a way to understand quantum mechanics–using hydrodynamic quantum analogs. In these experiments, researchers vibrate pools of silicone oil, which allows oil drops to bounce–and in some conditions, walk–indefinitely on the pool. By mixing in…
When the Meniscus Disappears
When we first learn about states of matter, we’re taught about three: solid, liquid, and gas. In a solid, atoms are held close to one another–typically, but not always, in an orderly lattice structure. In liquids and gases, atoms are free to slip, slide, bounce, and move. So what really separates a liquid from a…
Icy or Rocky Giants?
On the outskirts of our solar system, two enigmatic giants loom: Uranus and Neptune. In terms of mass and size, both resemble many of the exoplanets discovered in recent years. Within our own solar system, these planets are known as “icy giants,” but a new study suggests that moniker may be wrong. Pinning down the…
Swirling Without Blades
A ring of hydrogen bubbles rises, rotating clockwise, in this video of electrolysis. But there are no fan blades to cause this swirl, so why do the bubbles rotate? The answer is a Lorentz force induced by the electromagnetic set-up of the experiment. Watch to see how researchers manipulate the Lorentz force to affect the…