Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
A Colorful Glimpse
Peeking between the clouds, satellites caught a glimpse of a massive phytoplankton bloom off the coast of Greenland in May 2024. The tiny organisms may be visible only under a microscope, but gatherings like these stretch hundreds of kilometers and are visible from space. Like tracer particles in a flow, the phytoplankton outline the swirls…
“Frozen Waves”
Photographer Jan Erik Waider is a master of capturing incredible landscape imagery. In these videos, he uses a drone to film waves in the Baltic Sea gently undulating polygonal slabs of ice on the ocean surface. The interplay of light, color, and motion looks almost surreal, but nature is better than we credit at making…
Viscoelastic Vortex Street
When flow moves past a cylinder, vortices get shed in its wake. Known as a von Karman vortex street, this distinctive pattern is seen behind flags, islands, and even behind starships. Here, researchers are simulating flow of a viscoelastic fluid, where–unlike water or other Newtonian fluids–elastic stresses can build up. As the flow hits the…
Understanding Fish and Turbines
Fish detect turbulence in the water around them; among other things, this helps them avoid colliding with objects. Here, researchers are looking to understand how fish interact with underwater turbines. Experiments give them a set of trajectories that actual fish follow when dealing with the experimental turbine. But to understand what the fish is detecting,…
A Fungus That Freezes Water
Although water can freeze below 0 degrees Celsius, it requires a little help–in the form of a nucleation site–to do so. Often temperatures must dip well below 0 degrees Celsius for droplets to become ice. But a new study shows that at least one fungus forms proteins that help the process along. The proteins come…
Shocking Fizzy Jets
Many industrial processes break a fluid jet into droplets, like spray painting and ink-jet printing. Here, researchers examine an effervescent fluid jet made up of both liquid and gas. Like a fluid-only jet, this fizzy jet forms sheets, bags, ligaments, and droplets. As it breaks down, it creates a range of droplet sizes–both large and…
Insect Wings in Extreme Macro
Photographer Chris Perani is fascinated by the microstructures of insect wings, which he captures in “extreme macro” through focus stacking–letting us see wings in glorious micron-scale detail. In addition to giving insects their brilliant colors and irridescence, these structures serve another key role: they help insects stay dry. In a world where contact with water…
Melting Can Propel Icebergs
Icebergs have long served as a metaphor for not knowing what’s going on beneath the surface. Studies like today’s are a reminder of why that is. Researchers found that asymmetric icebergs–shaped, in this case, like a right triangular prism–can self-propel as they melt. Their shape forces cold, dense meltwater to slide down the surface, generating…
Schooling at Scale
Relatively simple visual and hydrodynamic signals are enough to make digital fish school in ways that resemble living ones. Here, researchers look at what happens when well-behaved schools of fish get too big. The researchers first demonstrate that their schools behave reasonably at one hundred members, either in a schooling configuration or a group milling…
Scrubbing Bubbles
Cleaning produce helps fruits and vegetables last longer and reduces the chances for foodborne illness. But it can be a difficult feat with soft, delicate foods like tomatoes, berries, or greens. Current methods often combine ultrasonic cleaning and chemicals like chlorine. Instead, researchers are looking to boost the cleaning power of bubbles themselves by giving…