Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Precipitation
Chemistry and fluid dynamics often go hand-in-hand. Here chemical reactions produce visible precipitates as one chemical drops into the other. The shapes that form are distinctly fluid dynamical, with vortex rings, plumes, and instabilities all appearing. In many applications, chemical reactions and fluid dynamics are tied inextricably to one another because the rate of chemical…
The Undisturbed Waters of Lake Kivu
Deep in Africa lies one of the world’s strangest lakes. Lake Kivu, over 450 meters in depth, is so stratified that its layers never mix. The upper portion of Lake Kivu consists of less-dense fresh water, which sits upon deeper layers of saltier water full of dissolved carbon dioxide and methane pumped into the lake…
Streamlining Circa 1936
This 1936 promotional film by Chevrolet explains the concept of streamlining objects to reduce their drag. And it actually does a pretty nice job of it, including some wind tunnel footage and table-top demonstrations. It’s also an amazing snapshot of the era, both in terms of engineering and the vision they had for the future.…
The Colors of a Thin Film
Soap bubbles and other thin films are colorful thanks to wave interference across their tiny thickness, but you may have noticed that only some colors appear. Others, like red, seem to be missing. In this video, Dianna digs into the details of wave interference and color theory to explain why we don’t see pure colors…
Jets Beneath Leidenfrost Drops
When a droplet impacts, it’s not unusual for converging ripples to form an upward jet, like the one seen here. But under the right circumstances, jets can form downward, too. This study looks at the ultrafast jets that can form beneath an impacting Leidenfrost drop. These Leidenfrost drops are striking a surface much hotter than…
“Monsoon 6”
The stunning power and beauty of our atmosphere comes to life in Mike Olbinski’s latest short film, “Monsoon 6”. Over the years, I’ve probably watched dozens of Olbinski’s videos, yet he still captures sequences that make me exclaim aloud as I watch. In this one, some of my favorites are the microburst at 2:17 and…
Why Masks Cut COVID-19 Transmission So Well
Face masks are an important tool for curtailing disease transmission, and this video explains how even imperfect masks do a much better job of protecting people than you may think. Strictly speaking, this video is not fluid dynamical — fluid dynamics plays more of a role in the details of what makes a mask effective…
An Intro to Liquid Crystals
There’s a good chance that the screen you’re using to read this uses liquid crystals, but how much do you know about this ubiquitous technology? Liquid crystals are fluids made up of molecules that orient into crystalline structures. Their usefulness for displays comes from the way they interact with light, changing the polarization of light…
Sensing Obstacles Through Flow
Mosquitoes, bats, and even eels use non-visual means to sense their environments. For mosquitoes, part of their obstacle avoidance comes from the exquisite sensitivity of their antennae, which are able to sense subtle changes in the air flow around them as they approach a wall or the ground. Researchers used this same technique to help…
Meandering
The banks of rivers are in constant flux, a pattern most easily captured from above. This satellite image shows a section of the Ivalo River in Finland, swollen with snowmelt after a winter of historic snowfalls. From above we see some of the river’s previous paths. This meandering is a natural result of secondary flows…