Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Squeezing Bubbles
An air bubble trapped inside a viscoelastic fluid is squeezed between two plates in this video, revealing a Saffman-Taylor-like fingering instability stemming from local stress concentrations. (Video credit: Baudouin Saintyves)
Winds Across the US
A collaborative project on data visualization brings to life the wind velocity data across the United States. The Wind Map is an interactive, nearly real-time indicator of wind conditions across the country, compiled on an hourly basis from the National Digital Forecast Database. Be sure to click through to see the data in motion. Observing the…
Micro Air Vehicle Flow Viz
A smoke wire shows the deformation of streamlines around a swept-winged micro air vehicle (MAV). These crafts typically feature wingspans smaller than one foot and, thus, never develop the type of flow fields associated with larger fixed-wing airplanes. This complicates theoretical predictions of lift and drag for MAVs as well as making them difficult to…
Visualizing Ocean Currents
Researchers used computational models of ocean currents to produce this video visualizing worldwide ocean surface currents from June 2005 through December 2007. Dark patterns under the ocean are representative of ocean depths and have been exaggerated to 40x; land topography is exaggerated to 20x. Notice the wide variety of behaviors exhibited in the simulation: some…
Vortex Cannon
Building a vortex cannon is a great way to demonstrate the power and longevity of vortex rings. As demonstrated here, it’s possible to create one with just a box with a round hole in it. Adding some smoke or stage fog helps visualize the rings. Vortex rings are found frequently in nature: volcanoes make them,…
Science Off the Sphere: Liquid Lenses
Astronaut Don Pettit delivers more “Science Off The Sphere” in his latest video. Here he demonstrates diffusion and convection in a two-dimensional water film in microgravity. He notes that the viscous damping in the water is relatively low and that, left undisturbed, mixing in the film will continue for 5-10 minutes before coming to rest, which…
Reader Questions: What Majors Study Fluids?
squky asks: Your blog has truly inspired me to want to major in the field of fluid dynamics, and for that I wholeheartedly thank you. But I’m having some confusion over which discipline (major) it falls under. Would it fall under physics or engineering? And if engineering, which type? (My two-year college doesn’t have an engineering…
Tornado in a Bubble
In this video, a miniature tornado-like vortex is created inside a soap bubble. Here’s how it works: after the first bubble is formed and the smoke-filled bubble is attached to the outside, he blows into the main bubble, creating a weak angular velocity, before breaking the interface between the two bubbles. As the smoke mixes…
How Dams Affect Rivers
This video shows how the installation of a dam can affect river flow and sediment transport. Before the dam is added, the flow is shallow and the sediment transport is uniform. The installation of the dam creates deep subcritical flow upstream and supercritical flow downstream. This means that wave information–like ripples–can propagate upstream on the…
Supersonic Flow
This video shows a sphere in a small supersonic wind tunnel at Mach 2.7. Once the tunnel starts, a curved bow shock forms in front of the sphere, close to but not touching the model’s surface. Areas of low pressure are visible behind the sphere, as is a weak shock wave caused by overexpansion in…