Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Mimicking Asteroids
In nature, objects like asteroids, black holes, and atomic nuclei can get distorted when spinning rapidly. Researchers are exploring these objects using a new model platform: particle rafts levitated by sound. The individual particles are less than a millimeter wide and tend to clump together due to the scattering of sound waves off neighboring particles.…
Pumping Waste
Sewage systems rely on gravity to remove waste from our homes and carry it toward treatment plants. But that constant downward slope can’t always be maintained. Sometimes we have to bring the sewage back up to the surface to process it. For that, modern systems rely on pumps and other equipment to move the challenging…
“Velocity”
In this short film by Vadim Sherbakov, macro shots of glittery ink and pigments look like astronomical vistas. The title of the film, “Velocity,” is spot on; every shot is full of flow and motion driven by the mixture of ink, alcohol, soap, and other fluids. That means lots of surface-tension-driven flow, and the glitter…
Moving By (Intestinal) Wave
A word of warning: today’s post includes visuals of digestion taking place in (non-human) embryonic intestines. Our bodies rely on waves driven by muscle contractions to move both fluids and solids, whether through the esophagus, the ureter, the fallopian tubes, or the intestines. In areas where mixing is unnecessary, those waves move in a single…
Tidal Vortices
Local topography in the Sea of Okhotsk funnels water to create some of the largest diurnal tides in the world — nearly 14 meters! The currents rushing past islands and outcrops create swirling vortices like the ones seen in this natural-color satellite image. In some places, you can even see multiple vortices, strung together into…
Perching Aerodynamics
When birds come in for a landing, they pitch back and heave their wings as they come to a stop in a perching maneuver. Some birds, researchers noticed, partially fold their wings during the move, creating what’s known as a swept wing. Curious as to the effect of this sweep, the team recreated the wing…
Merging Along Wires
As oil slides down two slowly converging wires, the droplets will merge into a sheet that stretches between both wires. When this happens can vary somewhat but occurs somewhere around the liquid’s capillary length. In the poster above, the leftmost image (not the illustration) shows three possible merger points. To the right of the image,…
“Haboob: A Decade of Dust”
From the right vantage point, an approaching dust storm — known as a haboob — can look downright apocalyptic. In this compilation of clips a decade in the making, photographer Mike Olbinski shows these storms in all their terrifying majesty. I love seeing how the cloud front overhead densifies as the dust below advances. Without…
Measuring Drag
After a noticeable rise in the prevalence of home runs beginning in 2015, Major League Baseball commissioned a report that found the increase was caused by a small 3% reduction in drag on the league’s baseballs. When such small differences have a big effect on the game, it’s important to be able to measure a…
Whistle Physics
Ever wondered how whistles work? Depending on the type of whistle, there are a few different phenomena in play, but the most fundamental one is the oscillation of a fast-moving air stream. Any small deviation in the air stream can set up a situation where the flow shifts side-to-side, and most whistles use this oscillation…