Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Reader Question: General Audience Fluids Books
nothing43-blog-blog asks: Do you know any good books on fluid dynamics? Not textbooks or handbooks, but more along the lines of what you’d find in the “popular science” section of the book store – accessible to a larger audience. Or maybe a good “history of fluid dynamics” book? That’s a great question! To be honest, I…
Cornstarch Monsters
The patterns formed when vibrating a liquid on a speaker cone are standing waves known as Faraday waves. With a large enough amplitude, this produces some very cool effects with a shear-thickening non-Newtonian fluid like oobleck. (It would actually be interesting to see what happens when you vibrate a shear-thinning liquid like shampoo…) This video…
Neutron Superfluids in Stars?
This image shows a composite X-ray (red, green, and blue) and optical (gold) view of the supernova remnant Cassiopeia A, located about 11,000 light years away. At the heart of this supernova remnant is a neutron star. After ten years of observations, astronomers have found a 4% decline in the temperature of this neutron star,…
Godspeed, Discovery!
The space shuttle, despite three decades of service, remains a triumph of engineering. Although it is nominally a space vehicle, fluid dynamics are vital throughout its operation. From the combustion in the engine to the overexpansion of the exhaust gases; from the turbulent plume of the shuttle’s wake to the life support and waste management…
Swimming Sandfish Lizards
Sandfish lizards can “swim” through granular flows like sand using an undulating, sinusoidal motion. Having studied this motion, engineers have built a robot that swims similarly through large glass beads and have now created a numerical simulation of the physics that matches the measured forces on the swimmer to within 8%. This type of flow…
Dancing Droplets
When a droplet falls onto a larger pool of the same liquid, it briefly sits on a layer of air that prevents coalescence. When that air drains away, the coalescence cascade–in which the droplet breaks into progressively smaller droplets until fully absorbed–begins. But if you vibrate the pool of liquid, the droplet bounces, effectively injecting…
Shock Waves
Flow visualization really can be considered a form of art. Though we fluid mechanicians are looking for physics, we’re quite aware of the beauty of what we study. The clips in this video mostly show transient shockwave behavior, including lots of shock reflection and even a few instabilities. It’s unclear what the speeds are, aside…
Rafting for Rocks
Rafting for Rocks Another look at the science behind the roaming rocks of Death Valley.
Rocket Launch Phenomena
The launch of the Solar Dynamics Observatory (SDO) last year provided a rarely seen glimpse of how shock waves affect the atmosphere during launch, but only recently have researchers explained the white column that seemed to follow SDO toward orbit. Simulations indicate that the shock waves from the rocket aligned the ice crystals in the…
Reader Question: Rotor Ships
lazenby asks: Can you explain how the magnus effect makes rotor ships move? When a spinning body is placed in a flow, the body experiences a force perpendicular to the direction of the flow. This is called the Magnus effect and is, for example, why baseballs, soccer balls, and tennis balls veer from the path we…