Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Growing Fingers
Branching, tree-like structures are found throughout nature. Take a thin layer of a viscous fluid pressed between two glass plates and inject a less viscous fluid like air and you’ll get branch-like structures. These are the result of the Saffman-Taylor instability and usually result in a fairly random outcome because of the instability’s sensitivity to…
Rolling Along
Leidenfrost drops – droplets deposited onto a surface much hotter than their boiling point – are known for their mobility. With the right surface, they can be propelled, trapped, and even guided through a maze, typically by directing the vapor layer that cushions them. But new work shows that these drops have internal dynamics that…
Twisting to Pack
One conventional method for packing granular materials is to tap them repeatedly, but a new study suggests that twisting is a faster method. Researchers poured thousands of dice into a cylinder, then twisted the container back and forth. When the acceleration caused by the change in direction exceeded a threshold value, the dice worked their…
Layered Latte Physics
Latte lovers may be familiar with the layered latte, a beverage with distinctive horizontal layers mixing espresso and milk, but you may not have taken the time to wonder how these layers form. Like many layering phenomena in our oceans, the layered latte is the result of double-diffusive convection. This means that there are two…
Liquid Sunbursts
Liquid sunbursts and swirling aquatic roses abound in photographer Mark Mawson’s work. Images like these are created from dropping ink into water and photographing it as it diffuses. For the roses, the tank is additionally stirred or spinning to create the vortex-like appearance. Check out his website for more striking images, including more billowing ink,…
A Hot Tub, Turned Fluidized Bed
Fluidized beds continue to be all the rage among science YouTubers, but Mark Rober supersizes his by turning a broken hot tub into a massive bath of bubbling sand. His video includes a nice explanation of how a granular material like sand gets fluidized as well as how to make your own miniature bed. One…
Cloud Flows
When viewed at the right pace, clouds can flow. This timelapse of fog over Mt. Tamalpais State Park near San Francisco shows clouds moving over the hills there. Physically, this flow is an example of a familiar phenomenon known as a hydraulic jump. It happens when a fast-moving flow moves into a region of slower…
Corrugating Water
The characteristics of a surface can have a major impact on the form a flow takes. The photo above shows a corrugated, almost pinecone-like water surface. It’s the result of a sheet of water flowing over a surface with alternating bands of hydrophobic (water-repelling) and hydrophilic (water-loving) properties. The water sheet narrows over hydrophobic sections…
Merch on Sale Through Dec. 15th
Reminder: FYFD merchandise is on sale through December 15th! If you’re like me and you’re still looking for holiday gifts, this is a great option 🙂 As a bonus, Redbubble is running a special sale today, December 11th. Use the code: DAYTWELVE at checkout to get an extra 25% off sitewide!
Flow Inside the Heart
Inside each of us is a remarkable and constant flow, driven by a muscle that’s always at work. As blood circulates through our bodies, it goes through a surprisingly varied journey. In the heart, as seen above, blood flow is very unsteady and quite turbulent, due to the beating pulse of the heart. As valves…