Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
The Two-Faced Splash
The way a sphere enters water depends on its size, speed, and surface properties. A hydrophilic (water-attracting) sphere behaves differently than a hydrophobic (water-repelling) one. But what happens when the object’s surface properties aren’t uniform? That’s the situation we see above. The dark line marks the two hemispheres of the sphere and their differing surface…
Eye of the Stellar Storm
AG Carinae is a bright, unstable luminous blue variable star. This rare type of star lives fast and dies young (by stellar standards) over only a few million years. During that time, it will occasionally blow off its outer layers in a violent eruption as a result of the ongoing tug of war between its…
Collective Motion in Grains
Flocks of birds and schools of fish swarm in complicated collective motions, but groups of non-living components can move collectively, too. In this Lutetium Project video, we learn about grains that, when vibrated, self-propel and form complex collective motions similar to those seen in groups of living organisms. A key feature of the grains is…
Visualizing Music With Ferrofluids
Here’s an ultra-cool DIY project: a Bluetooth speaker with ferrofluid music visualization! The music playing through the speaker drives an electromagnet, which causes the magnetic ferrofluid to pulse and shred in time with the music. Check out the video to see the project in action plus footage of the build coming together. (Video and image…
Bubbles Rising
Here we see high-speed video of air bubbles rising through sesame oil. The flow rate of air is just right for one bubble to catch up to and merge with the previous bubble. As it the trailing bubble pinches off from the valve, it shoots a small jet through itself and into the prior bubble.…
Snapping When Swollen
The Venus flytrap snaps shut on its hapless prey by swelling cells in its leaves with water. Under the added pressure of a fly’s footstep, the leaves’ snapping instability triggers, trapping the insect. Researchers are using similar physics to create jumping and snapping polymer gels, like the one seen below. To trigger the behavior, researchers…
Breaking Ocean Currents
Our global ocean currents move enough water to dwarf the flow of all Earth’s rivers. This worldwide circulation is driven largely by density and the movements of cold, salty water versus warmer, fresher water. The pump behind this action lies in the North Atlantic, where cold, salty water sinks down in the Atlantic Meridional Overturning…
Predicting Meteotsunamis
Meteotsunamis, or meteorological tsunamis, are large waves driven by weather rather than seismic energy. Although they occur along shorelines throughout the world, forecasters have very little infrastructure in place to predict or detect them. But a new study of an April 2018 meteotsunami on Lake Michigan (pictured above) has provided evidence that existing models may…
“Le Temps et l’Espace”
Filmmaker Thomas Blanchard creates a slow and dreamy fluid landscape in “Le Temps et l’Espace”. Made with ink and paints, the visuals are beautiful and serene. For similar works, be sure to check out the “fluids as art” tag! (Image and video credit: T. Blanchard)
Snail Locomotion
Snails and other gastropods move using their single muscular foot and a viscoelastic fluid they secrete. Muscular waves in the foot run from tail to head and are transmitted to the ground through the thin, sticky mucus layer without the snail ever fully detaching from the surface. The characteristics of this mucus layer are critical…