Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Reflections of the Storm
Fall and winter storms rip Lake Erie with violent waves. Photographer Trevor Pottelberg of Ontario captures the dramatic eruptions of mist and spray from these massive, turbulent waves. It’s amazing how many different characters a wave can take on. Just compare Pottelberg’s waves with those caught by Lloyd Meudell or Ray Collins. It’s almost hard…
Waves in Liquid Crystals
Liquid crystals are now ubiquitous in displays, but scientists are still discovering new properties for this state of matter. Here, a team explores nematic liquid crystals, whose rod-like shape rotates in three dimensions as they apply a voltage. The layer of liquid crystals is held between polarizing filters, creating regions of light and dark that…
Classifying Waves
In a lab, researchers create their waves in a long, clear-sided tank, where they can observe how the waves form, travel, and interact. To generate the wave, they use a plate, attached to a piston. Push the water at one end, and a wave forms. The type of wave that forms depends on both the…
Airflow in the Opera
Like so many other performers, the singers and musicians of New York’s Metropolitan Opera House were left without a way to safely perform when the SARS-CoV-2 pandemic began in early 2020. In search of safe ways to perform and rehearse, the Met turned to researchers at nearby Princeton University, who worked directly with the performers…
In a Box, Shaken
Tidal areas experience lots of oscillating, back-and-forth flow that builds up patterns in the sand below. In this experiment, researchers investigate a similar situation by filling a box with water and spherical particles, then shaking the box from side-to-side. Inside the box, the particles line up in chains that are perpendicular to the direction of…
Walking in the Wake
Flow visualization is an important tool in fluid dynamics, and scientists have many ways to capture and visualize flow information. But our methods are not the only — or even the best — ways to express a flow. Here, engineers teamed up with architects and artists to explore the flow behind an oscillating cylinder. When…
Why Moths Are Slow Fliers
Hawkmoths and other insects are slow fliers compared to birds, even ones that can hover. To understand why these insects top out at 5 m/s, researchers simulated their flight from hovering to forward flight at 4 m/s. They analyzed real hawkmoths flying in wind tunnels to build their simulated insects, then studied their digital moths…
Vietnam’s Emerald Isles
Vietnam’s Hạ Long Bay is home to more than 1,600 islands, many of them made up of mountainous limestone. The area is famous for its karst features, a type of terrain formed from highly porous, water-soluble rock. Over time, water dissolves and fractures the limestone, creating karst landscapes full of caves, springs, sinkholes, and fluted…
Never Break the Chain
Pour water out of a bottle, and you’ll see a jet with a shape that resembles chain links. Sometimes known as a “liquid chain,” this phenomenon occurs when water pours through a non-circular hole. It’s quite a complex behavior, as shown in this recent study of the nonlinear effect. Even so, the authors found that…
Pumping With Faraday Waves
Vibrate a liquid pool vertically, and it will form a pattern of standing waves known as Faraday waves. Here, researchers confine those waves to a narrow ring similar in size to the wave. The confinement causes a type of secondary flow — a streaming flow — beneath the water surface. As a result, the wave…