Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Bubble Trains in a Microchannel
Trains of bubbles flowing through a microchannel get distorted by periodic expansions and constrictions. In these images, flow is from left to right, and the narrow point of the channel is about 250 microns across. In narrow regions, the front of the bubble tends to move faster, while in wider areas, the back of the…
The Disintegrating Splash
A drop of blue-dyed glycerine impacts a thin film of isopropanol, creating a spectacular splash and breakup. The drop’s impact flings a layer of the isopropanol into the air, where air currents make the thin sheet buckle inward and break into a spray of droplets. Meanwhile, the liquid from the drop forms a thick, blue…
Snowmelt
Much of the rain that falls on Earth began as snow high in the atmosphere. As it falls through warmer layers of air, the snowflakes melt and form water droplets. The details of this melting process have been difficult to capture experimentally, but a new computational model may provide insight. The basic process has a…
Skyglow
Timelapse can be a beautiful way to highlight slow-moving flows like those in the sky. But it can also be valuable in showing differences in speed, as in the latest SKYGLOW Project video, “Colorado Serenade”, which shows the Colorado River and the skies overhead simultaneously. Timelapse highlights the difference in time scales between the fast-moving river…
Happy 2000 Posts!
Happy Friday and happy 2000th FYFD post! To celebrate, I played with surface tension and the Marangoni effect to make some art. For a run-down on the physics, check out this previous post on water calligraphy. Two thousand posts feels like a major milestone. Not everyone realizes this, but FYFD is a one-woman operation, so…
Riding Across Water
Humans may not be fast enough to run across water, but we’ve found other ways to conquer the waves. It’s even possible (though definitely not recommended) to ride across stretches of water on a dirt bike. To do so, you have to keep the bike (hydro)planing, and to understand what that means, let’s take a…
Martian Mantle Convection
Over geological timescales – on the order of millions of years – even hard substances like rock can flow like a fluid. Heat from the Earth’s core drives convection inside our mantle, and that fluid motion ultimately drives the plate tectonics we experience here at the surface. But most other planetary bodies, including those with…
Wave Clouds
Stripe-like wave clouds can often form downstream of mountains. This satellite image shows such clouds in the South Pacific where rocky mountains jut 600 meters (2,000 ft) above the sea. This disrupts air flowing east by forcing it to move up and over the island topography. The air does not simply settle back down on…
Plasma From a Jet of Water
There aren’t many naturally occurring plasmas in our daily lives; by far the most common one is lightning. So it’s something of a surprise that a stream of water hitting a material like glass is able to produce a toroid of plasma like the one above. The key here, though, is that the jet has…
Spinning Paint
Several years ago Fabian Oefner started spinning paint, and it’s been a perennial favorite online ever since. Here the Slow Mo Guys revisit their own paint-spinning antics by super-sizing their set-up. In some respects, it’s a little dissatisfying; as with their first time around, they don’t moderate the drill speed at all, so after the…