Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
The Cricket’s Chirp
Growing up, my summer nights often featured a chorus of crickets and bull frogs. Even now, the sound of those chirps reminds me of home. So how do crickets make their calls? As this video shows, it’s a matter of scraping the hard edge of one wing along a tiny series of spines, similar to…
Frozen Wavelets
Photographer Eric Gross captured these surreal alpine landscapes in Colorado’s Rocky Mountains. Although the lake’s surface appears to have frozen waves, the prevailing theory is that these mounds and divots occur when snowdrifts form atop the lake, melt and refreeze. Over multiple melting and freezing cycles, the lake builds up with what appear to be…
Spin Cycle
Rotational motion is a great way to break up liquids, as anyone who’s watched a dog shake itself dry can attest. That same centrifugal force is what allows this rotary atomizer to break liquids into droplets. Relative to the photos above, the atomizer spins in a counter-clockwise direction. This motion stretches the fluid flowing off…
Colorful Dissipation
Colorful eddies swirl in this short video from photographer Karl Gaff. Formed near the boundary at the bottom of the frame, these eddies act to dissipate some of the energy in the flow. Structures like these are key in turbulent flows, where energy must pass from large eddies to smaller and smaller ones until they…
Nitro Bubble Cascades
Fans of nitro beers — particularly Guinness’ stout — have probably noticed the fascinating cascade of bubbles that form as the beer settles. It’s a non-intuitive behavior — bubbles rise since they’re lighter than the surrounding fluid. So why do the bubbles appear to sink in these beers? There are several effects at play here. Firstly, overall…
Fluid Dynamics and Disease Transmission
Right now people around the world are experiencing daily disruptions as a result of the recently declared coronavirus pandemic. There is a lot we don’t know yet about coronavirus, though researchers are working around the clock to report new information. Today’s video, though a couple years old, focuses on an area of medical knowledge that’s…
Tranquilizer Darts in Slow Mo
Like most syringes, tranquilizer darts use pressure to drive flow. But where a typical syringe has that pressurization provided by a human driving the piston, tranquilizer darts must deploy without any hands-on action. As shown in the video above, this is achieved by pressurization prior to firing. The tranquilizer dart has a few key features.…
Submarine Canyons Focus Waves
In winter months Toyama Bay in Japan can get hammered by waves nearly 10 meters in height. These waves, known as YoriMawari-nami, pose dangers to both infrastructure and citizens, and, thus far, are not captured by typical forecasting models. A new study indicates that these waves have their origin in the particular topography of Toyama…
Pearls On a Puddle
Leave a drop of coffee sitting on a surface and it will leave behind a ring of particulates once the water evaporates. But what happens to a droplet made up of multiple liquids that evaporate differently? That’s the subject of this new study. Researchers mixed a volatile drop (isopropyl alcohol) with a smaller amount of…
The Sand Sea’s End
The northern extent of Africa’s Namib Sand Sea ends where the reddish dunes meet the Kuiseb River and the hard, rocky land on its other side. Within the sand sea, dunes stretch as high as 300 meters while the prevailing winds create and march them across the desert. Although dunes rarely occur in isolation, the…