Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
“Macrocosm”
In “Macrocosm” artist Susi Sie explores a liquid world of black and white. The two colors diffuse and mix to a soundtrack of “space sounds” recorded by NASA. (Most of these are probably ionic sound rather than sound as we’re used to, but even that is somewhat fluid dynamical.) The result is beautiful, surreal, and…
The Cheerios Effect
You’ve probably noticed that cereal clumps together in your breakfast bowl, but you may not have given much thought as to why. This tendency for objects at an interface to attract is known as the Cheerios effect, although it happens in more than just cereal, as Joe Hanson from It’s Okay to Be Smart explains.…
Forming Craters
Asteroid impacts are a major force in shaping planetary bodies over the course of their geological history. As such, they receive a great deal of attention and study, often in the form of simulations like the one above. This simulation shows an impact in the Orientale basin of the moon, and if it looks somewhat…
Lenticular Clouds
Lenticular clouds are peculiar enough that, for years, they’ve been mistaken for other things – often UFOs. These lens-shaped clouds tend to form near mountainous terrain, where air gets forced up and over the topology. If there’s a drop in temperature as the air rises, water can condense out to form the cloud. Once the…
Lighting Engines
Combustion is complicated. You’ve ideally got turbulent flow, acoustic waves, and chemistry all happening at once. With so much going on, it’s a challenge to sort out the physics that makes one ignition attempt work while another fails. The animations here show a numerical simulation of combustion in a turbulent mixing layer. The grayscale indicates…
Moving Fluids in the Right Direction
One challenge in creating miniature labs-on-a-chip is keeping fluids moving in the desired direction. The top image above shows red and blue droplets being moved toward one another on the top and bottom of a vibrating surface. Eventually, they meet and mix in the middle. To force the fluids in the right direction, the surface…
Flow Inside Convection Cells
Looking at convective cells, it’s easy to think that they are still and unmoving. But when you add particles, their inner flow becomes obvious. Warm, light fluid moves up through the center of each cell, skims along the surface, and then sinks at the edges of the cell after losing its heat at the cooling…
Rheoscopic Flow Vis
One of the great challenges in visualizing fluid flows is the freedom of movement. A fluid particle – meaning some tiny little bit of fluid we want to follow – is generally free to move in any direction and even change its shape (but not mass). This makes tracking all of those changes difficult, and…
The Mist of Champagne
If you’ve ever popped open a chilled bottle of champagne, you’ve probably witnessed the gray-white cloud of mist that forms as the cork flies. Opening the bottle releases a spurt of high-pressure carbon dioxide gas, although that’s not what you see in the cloud. The cloud consists of water droplets from the ambient air, driven…
Building Liquid Circuits
Building microfluidic circuits is generally a multi-day process, requiring a clean room and specialized manufacturing equipment. A new study suggests a quicker alternative using fluid walls to define the circuit instead of solid ones. The authors refer to their technique as “Freestyle Fluidics”. As seen above, the shape of the circuit is printed in the operating…