Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Aerial Sheep Flow
I may never get tired of drone videos of sheep herding. They are mesmerizing to watch and full of so many characteristics of flow. Like a compressible fluid, the herd squeezes together as it passes through a gate, then spreads and decreases density as it reaches the pasture. The sequence of sheep moving down the…
Digging Into Acoustic Levitation
Acoustic levitation is a fascinating phenomenon in which small objects, like the Styrofoam balls seen here, are levitated by a standing acoustic wave. In this image, a color schlieren system shows regions of increasing pressure with height (red) and decreasing pressure with height (green). The balls sit within the colored bands, indicating that they’re levitated…
Controlling Aerosols Onstage
Few industries saw more disruption from the pandemic than the performing arts. To help orchestras return to the concert hall in a way that keeps performers and audience members safe, researchers have simulated air flow and aerosols around musicians onstage. Some instruments — like the trumpet — are super-spreaders when it comes to aerosol production,…
How Sewers Work
One of the most important and underappreciated pieces of urban infrastructure is the sewage system. We rely on them to make our waste vanish, as if by magic. In reality, these systems are carefully engineered and built to be largely self-cleaning and future-proof. Gravity is the primary driver of the system, and engineers design the…
Benefits of Schooling
Though fluid dynamicists have long theorized about the hydrodynamic benefits of fish swimming in schools, nailing down the actual physics has been quite difficult. Fish rarely swim exactly as an experimenter would like, and measuring quantities like swimming efficiency in a living fish is tough to do. In the numerical realm, it’s tough to simulate…
Chasing the Storm
Towering mountains of convection and ominous colors are staples of Adam Kyle Jackson’s storm photography. His dramatic portraits of supercell thunderstorms highlight the majesty and power of these turbulent phenomena. Make sure to follow him on Instagram for lots more! (Image credit: A. Jackson; via Nat Geo)
Betelgeuse’s Flickering
Between November 2019 and March 2020 Betelgeuse, the red supergiant star in the constellation Orion’s left shoulder, experienced what’s being called the Great Dimming. Usually, the star is one of the ten brightest stars in the sky, often visible even in the suburban sprawl. But as of February 2020, it had dimmed by a factor…
Dripping With Particles
Adding just a little polymer to a fluid can make it viscoelastic and drastically change how it drips. A pure, viscoelastic fluid (left) necks down to a thin filament thanks to the polymers’ resistance to being stretched. But what happens when you add particles, too? That’s the focus of this recent study, which adds particles…
Ingenuity’s Dust Cloud
Mars is quite dusty. It periodically gets swallowed by planet-spanning dust storms, but it’s also home to regular dust devils whose size can put Earth’s to shame. Exactly how so much dust gets picked up by Mars’ incredibly thin atmosphere — only 1% of Earth’s — is still something of a mystery. So scientists were…
Spin Coating Capillary Tubes
To coat the interior of a capillary tube, you typically fill the tube with a viscous liquid, then pump air in to displace the liquid, leaving behind a thin film of the viscous fluid. Keeping that film uniform and thin is a challenge, though, since the pumps used often struggle to keep a consistent low…