Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Blowing Vortex Rings from Bubbles
When bubbles burst, we often pay attention to the retracting film and forming droplets, but what happens to the air that was inside? By placing a little smoke inside them, we can see. The air inside these bubbles is slightly pressurized compared to the ambient, and as such a bubble ruptures, its air gets pushed…
Twirling Liquids
What do you get when you spin a splash? I expect the result is a lot like these whirling fluid structures captured by photographer Hélène Caillaud. I love the fantastical shapes she creates as sheets and filaments are flung outward. These liquid sculptures look like everything from the perfect martini glass to the skirts of…
Waltzing Defects
Liquid crystals are a peculiar state of matter with both liquid and crystalline properties. In this video, a microfluidic device breaks water into droplets surrounded by a shell of liquid crystal. Because the molecular structure of the liquid crystals is helical and cannot pack neatly in a spherical shell, there are visible defects in the…
Inside the Fire Lab
Fire plays an important role in nature, one with which humanity must live without controlling fully. After several disastrous historic wildfires in the American West, the U.S. Forest Service established its own fire lab, where research foresters can study flames firsthand. This video takes us inside the Fire Lab for a look at the facilities…
Kneading Dough
Kneading bread dough is something of an art. The process binds flour, water, salt, and yeast into a network that is both elastic and viscous. It also traps pockets of air that will determine the texture of the final loaf. Underknead and the bubbles won’t form; overknead and the result will be a dense loaf…
Blooming Deposits
Evaporate a droplet full of silica nanoparticles, and you’ll get beautiful, flower-like films. As the water evaporates, dry nanoparticles build up in a solid deposit. The evaporation creates a pressure gradient that pulls toward the center of the drop, forcing the deposit to bend. As stress builds in the deposit, cracks form petal-like segments. The…
Creating Star Wars-Like Volumetric Displays
Despite their ubiquity in science fiction, volumetric displays — three-dimensional displays visible from any angle — have been tough to create in real life. But a team from the University of Sussex has made impressive strides using a system based on acoustic levitation. Here’s how it works: an array of ultrasonic speakers levitates and moves small…
“Ornitographies”
If birds left trails in the sky, what would they look like? This is the question that haunted photographer Xavi Bou and inspired him to create his “Ornitographies” series. Using video of birds in flight, he combines frames to construct these snapshots of flight. In them, birds become streaklines feathered with wingbeats. I love how the technique highlights the…
Drying Out
Look closely at old paintings, and you’ll notice arrays of tiny, straight cracks that form as the paint dried. This sort of pattern formation during drying is not unusual. Here we see the patterns formed when a thin layer of hydrogel sandwiched between two glass plates dries. As the water evaporates, stress builds at the…