Flex Pen and Ink
It’s no secret that I’m a fan of fountain pens. They’re just one way I like to have little celebrations of fluid physics in my everyday life . (Video and image credit: Flexperiments)
FYFD
Celebrating the physics of all that flows. Ask a question, submit a post idea or send an email. You can also follow FYFD on Twitter and YouTube. FYFD is written by Nicole Sharp, PhD. If you’re a fan of FYFD and would like to help support the site and its outreach, please consider becoming a patron on Patreon or giving a donation through PayPal with the button below. Your support is much appreciated!
Latest posts
Capillary Slinkies
Nature is full of helical fibers, including in plants and bird feathers. In this study, researchers explore how these soft springs react to droplets . (Image and research credit: B. Bhatt and A. Carlson )
Levitating By Squeeze Film
We’ve seen a few different kinds of levitation here over the years, including via acoustic waves, aerodynamics, and Leidenfrost effect. Here, Steve Mould describes something a bit different: a levitation squeeze film driven by ultrasonic transducers . (Video and image credit: S. Mould)
Dragonfly Dogfights
Like fighter pilots of old, male dragonflies engage in aerial combat where each tries to outmaneuver the other to keep a sight on their rival’s tail. A recent study observed this combat in the field and uncovered some surprising similarities to dogfighting . (Image and research credit: S. Fabian et al. ; via Ars Technica )
Blowing Droplets Apart
In raindrops, ink-jet printing, and spray painting, droplets get broken apart y the air flowing around them. Here, researchers investigate how a jet of fluid can push a droplet from its perch, or–with enough momentum–shatter the droplet . (Video and image credit: S. Jain et al. )
Salt and Dunes
Photographer Barbara Brown captured these striking aerial views in Namibia. Coastal dunes and saltworks feature in the photos from Walvis Bay, where wind, waves, evaporation, and humankind have shaped the landscape. (Image credit: B. Brown/ IAPOTY ; via Colossal )
How Corals Stir
Reef-building coral polyps constantly stir the water around them with dense carpets of microscopic hair-like cilia. The beating of the cilia helps polyps feed while also pushing away sediment and debris . (Image and research credit: S. Selvan et al. ; via APS )
The Subtleties of Pipe Flow
If you put a thumb over your hose’s outlet, you get a faster jet, but how does that affect the flow rate? That’s the question Grady starts from in this Practical Engineering video exploring pipe flow physics . (Video and image credit: Practical Engineering)
Screening for Sleep Apnea
Snoring and sleep apnea–a condition where aeroelastic flutter obstructs the airway and stops breathing during sleep–often go hand-in-hand . (Image credit: L. Cline ; research credit: H. Li et al. ; via Physics World )
Microplastics in the Water Column
Of the more than 9 billion metric tons of plastic that’s been produced, a mere 9% has been recycled. About 12% has been incinerated, and the remainder is just out there–in our homes, our landfills, and, unfortunately, in our oceans. (Image credit: iStock/dottedhippo ; via Eos )
"Supercell"
A supercell thunderstorm in New Mexico appears almost otherworldly in this photo from Dennis Hualong Zhang . (Image credit: D. Zhang; via ILPOTY )
Ice Giant or Magma Ocean World?
Uranus and Neptune–known as our system’s ice giants–are our least explored planets. “Ice giant” is one structure that matches the limited measurements we have from these planets, but, as today’s preprint study points out, it’s not the only one . (Image credit: NASA ; research credit: E. Young et al. (preprint); via Gizmodo )
Giant Water Balloon to the Face
It’s the summertime, so Gav and Dan of the Slow Mo Guys are back to experimenting with giant water balloons. In this video, they send several careening down a slope into Dan’s face . (Video and image credit: The Slow Mo Guys)
Inside an Espresso Bed
When pulling a shot of espresso, there are complicated physics at play. The ground coffee is tamped into a puck-like bed of grains, through which high-temperature, high-pressure water is forced . (Image credit: top - R. Wicks , experiment - J. Foster et al. ; research credit: J. Foster et al. ; via Physics World )
Canyon Swirls
For much of the year, Cañon Fiord in the Canadian Arctic lies under ice and snow, but in the summer melt season, colors peek out. Here sea ice and sediment swirl in the fjord in eddies that are kilometers wide . (Image credit: L. Dauphin; via NASA Earth Observatory )
Múlajökull
Iceland’s Múlajökull glacier is prone to sudden surges, where rapid ice flow is interspersed between periods of quiescence or retreat. The isolated nature of the glacier and its marshy surroundings make approaching on foot almost impossible, but photographer Dani Guindo captured gorgeous aerial images of the glacier’s many rivulets ribboning about the landscape it’s carved .…
Convection Inside the Mantle
Most of what we know about Earth’s interior comes from observing how seismic waves–mostly from earthquakes–bounce around. As our observations have gotten better–more seisometers, better imaging techniques–scientists have identified two large anomalies sitting near the bottom of the mantle . (Image credits: E. Garnero and C. Richardson ; see also Physics Today )
Even Penguins Love Bubbles
Walter, a young African penguin at the New York Aquarium, loves soap bubbles. In fairness to Walter, so do most people (Image credit: I’ve met. There’s just something that feels a bit magical about these ephemeral rainbow spheres that pop at a (dry) touch . (Image credit: New York Aquarium ; via PopSci )
Where Waves Carry Plastics
The classic theory of steady wave motion predicts a phenomenon called Stokes drift, in which particles spread horizontally in the direction of wave travel. That means that something like microplastics will drift in the direction that waves are traveling. But in the real world, ocean waves aren’t quite so neat and unchanging. A new study looks at what happens when waves are decaying in…
Making Quieter Shock Waves
NASA’s X-59 aircraft is intended to demonstrate supersonic flight without the boom. Although we haven’t yet heard its “sonic thump,” we do have a glimpse of what to expect, thanks to wind tunnel tests . (Image credit: NASA; see also: Ars Technica , M. Ahaus et al. )