Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Droplets From Speaking
Illnesses like COVID-19 can spread through droplets and aerosols produced by coughing, sneezing, or even speaking. New research looks at how regular speech patterns produce a spray of droplets. Researchers found that pronouncing many consonants causes a sheet of saliva to form between the speaker’s lips. That sheet stretches into filaments that then break into…
Chaos in the Lagoon Nebula
Even on the scale of light-years, fluid dynamics plays a role in our universe. This photograph shows the Lagoon Nebula, where stars, gas, and dust are battling for supremacy. Jets from young stars push the dust left from supernova remnants into a chaotic patterns, and the high-energy particles streaming from the youthful stars illuminate interstellar…
“Colors”
Paint, soap, bleach, oil, and oat milk combine to create the gorgeous colorscapes of Thomas Blanchard’s short film “Colors”. Watch as droplets burst and waves of color flow past. It’s a lovely break from whatever you’re dealing with at the moment, and at less than 3 minutes long, you can spare the time! (Image and…
Rings of Ice
Heavy rains followed by a sudden freeze can produce icy puddles like this one. Because the pool was shallow to begin with, it likely froze rapidly. As the temperature continued dropping, the newly-formed ice contracted; the ring pattern of the cracks tells us the stress in the ice was primarily radial. Once formed, the cracks…
Droplets on Inclined Walls
When a droplet impacts an inclined surface, it spreads asymmetrically. The splash shape is largely elliptical, as researchers found when modeling such impacts over a range of inclination angles. Understanding such splash patterns is important not only for industrial applications like printing but in areas like forensic science. (Image and research credit: P. García-Geijo et…
A Primer on Blood Pressure
Some of the most important fluid dynamics goes on every moment inside our bodies. After only a few weeks of gestation, the human heart begins its lifelong task of pumping blood throughout tens of thousands of kilometers’ worth of blood vessels. One of our simplest methods for tracking the health of this critical system is…
Freezing Splats
When a drop hits a surface colder than its freezing point, there’s a competition between retraction and solidification that determines the final shape of the splat. For many materials, like wax or soldering metals, the contact angle between their liquid and solid phase is zero, so there’s no major shape change once solidification begins. But…
Coffee, Magnified
Sometimes it’s nice to see a new perspective on something familiar. These images show oils from coffee beans suspended in hot water, as seen under 40x magnification. The crystals you see are caffeine and the variety of shapes in the oil blobs is due to being sandwiched between two layers of glass. You can check…
A Colorful Portrait of Flow
This gorgeous, natural-color image shows Lake Balkhash in southeastern Kazakhstan. In early March, the ice on the lake was beginning to break up, revealing glimpses of swirling sediment below the water’s surface. In contrast, the smaller lakes and ponds of the surrounding area remained frozen amidst the wintery browns of the nearby desert and wetlands.…