I love when science and art come together, which is why I’ve long been a fan of the Flow Vis course at CU Boulder. Some of my earliest posts on FYFD date from previous editions of the course. Here are a few of my favorite images from the Fall 2019 class, from the top:
For those in the Front Range area, the Flow Vis class will be showcasing their work on Saturday, December 14th at the Fiske Planetarium. Snacks are at 4:30 pm and the show starts at 5 pm. For those not nearby, you can peruse the art from this semester and previous ones at your leisure online. (Image credits: colorful ferrofluid – R. Drevno; falling oobleck – A. Kumar; droplets – A. Barron; macro ferrofluid – A. Zetley)
Plate tectonics is a relatively young scientific theory, only gaining traction among geologists in the late 60s and early 70s. One key tenet of the theory is subduction where plates meet and one is forced down into the mantle, like in this illustration of the subduction zone near Japan. In early incarnations of the theory what happens to that subducting slab of rock once it’s in the mantle were ignored. But over the decades, geologists have built maps of the interior of our planet through the seismic waves they record. What they’ve found is that the continental chunks that break off and sink can have long-lasting effects.
Beneath the Earth’s crust, the mantle behaves like an extremely slow-moving fluid under incredibly high temperatures and pressures. It can take tens of millions of years, but those broken slabs sink through the mantle, dragging fluid with them. This creates a large-scale flow known as a mantle wind, which can have far-reaching effects at the Earth’s surface. Through modeling and simulation, geologists have found these deep mantle flows may explain why mountain ranges like the Himalayas and Andes didn’t grow until millions of years after their plates collided and why earthquakes sometimes occur far from plate boundaries. For more, check out this great article from Ars Technica. (Image credit: British Geological Survey; via Ars Technica; submitted by Kam-Yung Soh)
In his short film, “Magic Fluids,” Roman De Giuli uses cyan, magenta, and yellow paints to generate a rainbow of macro colors. All the fluid motion you see is a practical effect, painstakingly created by layering paints and flow mediums of different densities. Like in Siqueiros’ “accidental painting” technique, the less dense paints will eventually rise through the upper layers and spread. De Giuli uses the effect for its motion, but the same physics is key for many artists who use acrylic pouring to paint. (Video and image credit: R. De Giuli)
Wildfires are an ongoing challenge in the western United States, where droughts and warmer conditions have combined with a century of fire suppression to form perfect conditions for monstrous fires. It’s long been understood that ambient winds can drive spreading fire, but the connection between wildfire and wind is more complicated than this.
The heat of a fire drives buoyant air to rise, creating tower-like updrafts in a flame front. We see this both in the shape of the grass fire above, and in the wind vectors of a simulated grass fire in the lower image. Between those towers are troughs where cooler ambient wind is drawn in to replace the rising air. How a fire spreads will depend on the speed, direction, and temperature of these winds. A hot wind fed by the fire’s heat will raise the temperature of fuel in unburned areas, bringing it closer to ignition. In contrast, cooler ambient winds can hinder a fire by keeping nearby grass and twigs too cool to ignite. (Image credit: fire – M. Finney/US Forest Service; simulation – R. Linn; research credit: R. Linn et al.; for more, see Physics Today)