Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
The Challenges of Blowing Bubbles
Although every child has experience blowing soap bubbles with a wand, only in recent years have scientists dedicated study to this problem. It turns out to be a remarkably complex one, with subtleties that can depend on the size of the wand relative to the jet a bubble-blower makes as well as the speed at…
The Flutter of Kelp
Many species of kelp change their blade shape depending on the current they experience. In fast-moving waters, the kelp grows flat blades, but when the water around them is slower, the same plant will grow ruffled edges on its blades. In a slow current, the ruffled version’s extra drag causes it to flutter up and…
Breaking Up Drops
Lots of applications – from rocket engines to ink jet printing – require breaking large droplets into smaller ones, so there are many methods to do this. Some techniques rely on fluid instabilities, others use ultrasonic vibration. But one of the most effective methods may also be the simplest: placing a mesh between large drops…
Foam and Flow
Fluid dynamics often play out on a scale that’s difficult to appreciate from our earthbound perspective, but fortunately, we have tools to aid us. This natural-color satellite image shows Rupert Bay in Quebec, where fresh water stained with sediments and organic matter (right) flows into the saltier water of James Bay (left). White filaments at…
From Firenado to Water Spout
Just a few years ago, fire tornadoes were almost fabled because they were so rarely captured on video. Now, with worsening wildfire seasons and cell phone cameras everywhere, there are new videos all the time. This video captures a fire tornado that sets off a water spout as it reaches the river (~1:15 in). Neither…
Icy Penitentes
At high, dry altitudes, fields of snow transform into rows of narrow, blade-like formations as tall as 2 meters. Known as penitentes – due to their similarity to kneeling worshipers – these surreal snow sculptures form primarily due to solar reflection. Surrounded by dry air and intense sunlight, the snow tends to sublimate directly into…
Soap Film Filter
Inspired by the self-healing properties of soap films, scientists have created a liquid filter capable of trapping small particles while allowing larger ones to pass through. Instead of filtering particles by size, as conventional filters do, this liquid membrane filters particles by kinetic energy; only large, fast-moving objects pass through while slower and smaller ones…
Shock Waves in the Solar Wind
The empty space of our solar system is not truly empty, as we’ve discussed previously. For one, there’s a fast-moving flux of charged particles – the solar wind – that flows constantly from the Sun. Sometimes these solar wind particles encounter their interstellar equivalents – charged ions from outside our solar system – and exchange…
Different Kinds of Boiling
When you put a pot of water on to boil, you probably don’t give much thought to the process. In our daily lives, we pretty much only see one kind of boiling: the sort where lots of small bubbles form on a hot surface and then rise. That’s nucleate boiling (top image), and it’s typical…
“Muses”
What looks like Baroque paintings are, in fact, underwater photographs in Christy Lee Rogers’ new “Muses” series. By photographing her models underwater at night, Rogers creates a unique, almost dream-like atmosphere that owes its effect to the interplay of light and water. The billowing fabric and chaotic motion come from the water itself, and the dramatic…