- Profile
“The Goblet of Fire”
Sometimes the mundane events of life hide extraordinary phenomena. This award-winning photograph by Sarang Naik shows yellow-brown spores streaming off a mushroom during monsoon season. The plume is abstract and beautiful; you could easily mistake it for the flames of an Olympic torch. But common as they are, the lowly mushroom hides interesting depths. To…
Pump Problems
Pumps are a critical piece of infrastructure, but to keep them operating, engineers have to account for several potential pitfalls. In this Practical Engineering video, Grady discusses some of the common fluid dynamical effects that can destroy a pump and its performance. As you’ll see in the video, a lot of the challenges boil down…
Contact-Line Dissipation
In the confines of a narrow tube, a flow’s energy gets dissipated in two places: inside the bulk fluid and along the contact line. The former is standard for all flows; viscosity acts like internal friction in the fluid and dissipates a flow’s kinetic energy into heat. Contact line dissipation is trickier. While it isn’t…
Mud Pots
Mud pots, or mud volcanoes, form when volcanic gases escape underlying magma and rise through water and earth to form bubbling mud pits. I had the chance to watch some at Yellowstone National Park a few years ago and they are bizarrely fascinating. In this Physics Girl video, Dianna recounts her adventures in trying to…
Devising Greener Chemistry
Not all microfluidic devices use tiny channels to pump and mix fluids. Some, like the Vortex Fluidic Device (VFD), conduct their microfluidic mixing in thin films of fluid. The VFD is essentially a tube spinning at several thousand RPM that can be tilted to various angles. Coriolis forces, shear, and Faraday instabilities in the thin…
Inside Old-Fashioned Butter
Today’s video is a little different: it’s an inside look at a butter-making shop in France that uses traditional nineteenth-century methods to process the butter. Watching workers fold and shape 50 kilos of butter is mesmerizing, and it highlights the amorphous, pseudo-fluid nature of the butter. Yes, the butter holds its shape like a solid,…
Suspended Sediments in Lake Erie
Lake Erie’s Long Point is outlined in turquoise in this natural-color satellite image. The pale color is likely due to limestone sediments in the shallow waters getting resuspended by a seiche or other disturbance. A seiche is a standing wave that forms in a partially- or fully-bounded body of water; in Lake Erie they are…
Martian Polar Troughs
Mars‘s northern pole is capped by a spiral-like pattern of deep troughs that are covered by carbon dioxide ice in winter but visible from orbit in summer. A new study posits that the spiral formed by wind erosion, exposing layer after layer of Martian geology. The center of Mars’s polar cap is higher in the…
Unusual Insects Taking Off
What do you do when you’re an insect researcher with a high-speed camera? Why, film all sorts of unusual insects from your backyard as they take off and fly! Here Dr. Adrian Smith of Ant Lab shows us a slew of insects that are not unusual for their rarity — you can probably find many…
How Frogs Block Unwanted Noise
In a crowded room, it can be hard to pick out the one conversation you want to hear. This so-called “cocktail party problem” is one animals have to contend with, too, when a noisy landscape can obscure the calls of potential mates. American green tree frogs have a clever solution to the problem: inflating their…