Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Mammatus Clouds
Mammatus clouds are a relatively rare and dramatic variety. One advantage of living in Colorado is that I see them somewhat often, especially during our stormy springs and summers. This video by Mike Olbinski features a dramatic skyscape of mammatus clouds (here in Colorado, natch) at sunset. Although they’re often associated with stormy weather, there’s…
Celebrating Turbulence
Laminar flow is easy to love, but turbulence is a far richer phenomenon. That’s the premise behind Veritasium’s new video (and, yes, I agree with him). In the video Derek provides a nice introduction to turbulence, including a checklist of qualities a turbulent flow must have. Personally, I don’t classify flows as simply being either…
Scaling High-Speed Impacts
The impact of a solid object into a bed of grains is a major topic in many fields from ballistics to astronomy. Researchers study these impacts experimentally using photoelastic disks, which display visible stress patterns when placed between polarizers. The lightning-like patterns you see above reveal how forces propagate inside the grains as the object…
Toad Singing
With spring heading into summer, many parts of the United States enjoy a nighttime chorus of frogs and toads. These amphibians are singing to attract mates and delineate territory. Some, like this American toad, sing from the water, and the vibration of their vocal sac creates ripples that last as long as they’re vocalizing. The…
Dissolving Caramel
In nature, erosion patterns are driven by the interactions of flow and topography. Here, researchers study that process in the lab by placing an inclined block of caramel in quiescent syrup and watching as it dissolves. Initially, the bottom surface of the block develops regularly-spaced plumes — the dark lines seen in the first image.…
“As Above”
In Roman Hill’s “As Above,” we see expansive celestial landscapes: nebulae, the corona of a star, and expanding interstellar dust clouds. Except, in reality, we are watching fluids undergoing a chemical reaction, on a canvas only 8 square millimeters in size. It’s a fun — and beautiful — reminder that the patterns of physics repeat…
How Did Pterosaurs Fly?
One of my favorite aspects of fluid dynamics is how well it pairs with so many other fields, from mathematics and space exploration to biology, medicine, and even paleontology. That last field is key to today’s question, namely: how did a prehistoric reptile the size of an F-16 manage to fly? As Joe’s video describes,…
Measuring Contaminants in Drops and Bubbles
Rising bubbles and droplets are common in many chemical and industrial applications. But just a tiny concentration of contaminants on their surface can completely alter their behavior, disrupting coalescence and slowing down chemical reactions. Historically, it’s been hard to measure the level of contamination in these some drops and bubbles, but a new study outlines…
#ShutDownSTEM in Support of Black Academics
Academia, like every part of our society, has a race problem. Today, I’m joining in the effort to change that by taking a break from business as usual and examining the issues facing my Black colleagues and what I can do to change them. I encourage you to do the same, and if you stick…
The Eerie Singing of the Golden Gate Bridge
Recent changes to the Golden Gate Bridge’s guardrails have created a new soundscape in the Bay Area. Under high winds, the bridge gives off an eerie, otherworldly wail that can be heard even miles away. The new guardrails are substantially thinner than the previous ones, which reduces the wind load the bridge has to endure.…