Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Pyrocumulus on the Horizon
View this post on Instagram Time lapse of yesterday’s rare Pyrocumulus clouds churning high above the Idyllwild hellscape, bringing with them strong winds, the threat of lightning and turbulence that can make it difficult for aircraft to help firefighters on the ground. As fire spreads, intense heat causes a rush of hot air and particulate…
What Keeps a Foam Intact
Beer, soda, soap, meringue – foams are everywhere in our lives. But have you ever wondered why some foams disappear so quickly while whipped egg whites stick around? That’s the subject of this Gastrofisica video, which is in Spanish but has English captions. Foams form when air gets introduced into a liquid, but for those…
A Burst of Microdroplets
If you hold a bubbly beverage like champagne or soda near your face, you’ll feel a light mist of tiny, nearly invisible droplets.These droplets form when bubbles reach the surface and pop, generating a tiny jet that ejects an even tinier droplet, as shown in the animation above. This process is remarkably common; its occurrence…
Swimming, Cycling, and Sailing
Summer brings with it lots of great sports, and whether you love riding a bike, sailing a boat, or just hanging out at the pool, our latest FYFD/JFM video has something for you. Want even more sports physics? Check out the Olympic series we did for the London and Rio games. And if you’re looking…
“Le Temps”
Thomas Blanchard is back with another beautiful music video. This one features ink cascading over various shapes underwater. Lots of tiny mushroom-shaped Rayleigh-Taylor instabilities here caused by the ink’s greater density compared to the surrounding water. There are also some lovely examples of transitional flow, especially around the spheres. Initially, flow over the spheres looks…
Convection Without Heat
We typically think of convection in terms of temperature differences, but the real driver is density. In the animations above, cream sitting atop a liqueur is undergoing solutal convection – no temperature difference needed! The alcohol in the liqueur mixes with the cream to form a lighter mixture that rises to the surface. The lower…
A Viscous Splash
The splash of a drop may be commonplace, but it is still a mesmerizing and fertile phenomenon. When it comes to splashing, scientists are still learning how to predict the outcome. Here a drop of silicon oil impacts a film of silicon oil with an even higher viscosity. The momentum of that impact creates a…
The Kaye Effect
Allow a stream of shampoo to fall into a pile and you’ll catch a glimpse of the bizarre Kaye effect. A jet of shampoo will briefly rise up before becoming chaotic and falling. The key to this behavior is the shear-thinning of the shampoo. When the shampoo is just sitting on a surface, it’s quite…
When Sound Makes You Vertiginous
For some people, a musical tone is enough to induce vertigo and feelings of being drunk. These individuals often have a small hole or defect in the bone that surrounds the canals of the inner ear. Normally, the fluid inside these canals reacts when we rotate our heads, triggering a counterrotation of our eyes that…
Breaking With a Wave
For rocket combustion and other applications, like watering your lawn with a hose, a stream of fluid may need to be broken up into droplets. While simply spraying a liquid jet will make it break up, waving that jet back and forth will break it up faster. A recent study simulated this problem numerically to determine…