Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Beneath the Cavity
When a drop falls into a pool of liquid, it creates a distinctive cavity, followed by a jet. From above the surface, this process is well-studied. But this poster offers us a glimpse of what goes on beneath the surface, using particle image velocimetry. This technique follows the paths of tiny particles in the fluid…
“Elements”
Photographer Mikko Lagerstedt specializes in Nordic landscapes, like the windswept snow seen here. I love the way he’s captured the snow that gets picked up and blown by the wind. Notice the hazy layer of snow hovering over the foreground. This snow is saltating, just as sand does in the desert. When flakes get picked…
Mixing With E. Coli
What happens when a flow meets swimming micro-organisms? Does the flow affect the swimmers? And how do the swimmers affect the flow in turn? Those are the questions behind the experiment seen here. The apparatus contains a thin layer of saline water with swimming E. coli. Electromagnetism is used to mix the fluid in an…
A Starry Nursery
This mountain of interstellar gas and dust lies in the picturesque Eagle Nebula. Though it appears solid in this near-infrared image from JWST, the density of the structure is actually quite low. Jets and solar winds from the glowing, young stars inside the region sculpt the pillar’s shape. Over the next 100,000 years, the stars’…
Surface Fat Gives Chocolate’s Mouthfeel
Understanding the interactions of food and our mouths is incredibly difficult. There are lots of changes going on: shape changes from chewing, viscosity changes as saliva lubricates the food, and, sometimes, phase changes from the heat of our bodies. Add to that the sensitivity of our papillae-covered tongues, and it’s a lot to manage all…
Founts of Enceladus
In its exploration of Saturn, Cassini discovered that the moon Enceladus is home to icy eruptions. Beneath its shell of ice, Enceladus has a global ocean of salty liquid water. The average thickness of the ice is 20 kilometers, putting the ocean seemingly out of reach — except at the moon’s southern pole, where icy…
Paint Ejection
Shaking paint on a speaker cone and filming it in high speed is an oldie but a goodie. Here, artist Linden Gledhill films paint ejection at 10,000 frames per second, giving us a glorious view of the process. As the paint flies upward, accelerated by the speaker, it stretches into long ligaments. As the ligaments…
Stabilizing Paper Airplanes
Making a good paper airplane is tough. Drop a simple sheet of paper and it will tumble and flip its way to the floor instead of gliding. The folds of a proper paper airplane add weight in just the right spots to stabilize its flight and let it glide smoothly through the air. To better…
How Spillway Gates Work
Dams and reservoirs need a way to control their water level, and for many, that’s managed using spillway gates. In this video, Grady from Practical Engineering introduces several types of spillway gates, including their advantages and disadvantages. As always, he’s got neat tabletop demonstrations of each type, and he digs into the practical issues engineers…
Flamingo Fluid Dynamics
Flamingos strut and dance and bob, but there’s more to these comical birds than meets the eye. Flamingos can thrive in nutrient-poor environments that other birds eschew, like salt flats and alkaline lakes. Their secret, it turns out, is a mastery of fluid dynamics. Researchers studying the behaviors of the Nashville Zoo’s flamingo flock discovered…