Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
The Fluid Dynamical Sewing Machine
Anyone who has poured a viscous fluid like honey or syrup will have noticed its tendency to coil like rope. A similar effect is observed when a viscous fluid stream falls onto a moving belt. The photos above show some of the patterns seen in these “fluid-mechanical sewing machines” depending on the height of the…
Sea Surface Temperatures
This video shows sea surface temperature results and their seasonal variation from a numerical simulation modeling circulation in the atmosphere and oceans. Modeling such enormous problems requires the development of reasonable models of the turbulent physics, clever algorithms to quickly progress the solutions, relatively low-fidelity (a single grid node may cover tens of kilometers), and enormous…
Sunset Vortices
Wingtip vortices roll up in the wake of this U.S. Coast Guard C-130J. At the edge of a wing high-pressure, low velocity air is able to creep around the edge of the wingtip toward the low-pressure, high-velocity air atop the wing. This creates a swirling vortex that trails behind each wing, made visible here by…
The Chaos of a Bouncing Droplet
This video explores chaos in a bouncing droplet. A drop of silicon oil bounces on a vibrating bath of oil; the thin layer of air injected with each bounce between the droplet and bath keeps them from coalescing. Initially, the droplet behaves like a bouncing ball, jumping once per oscillation. As the vibration amplitude increases,…
Canyon Fire Timelapse
Wildfires continue to burn across Colorado and other parts of the United States. This timelapse video shows 5 days worth of the Waldo Canyon fire. Smoke billows through the night and day, with diurnal temperature changes and winds affecting whether the turbulent plumes rise high or hover on the horizon. It is hard to describe…
How the Sun Drives the Earth
This video describes how the sun’s energy drives wind and ocean currents on earth. As solar winds stream forth from the sun, our magnetosphere deflects the brunt of the impact (creating auroras at the poles) while the atmosphere, land masses, and oceans absorb thermal energy from the sun’s light. Because of our cycles of day…
Traffic Fluid Dynamics
What does traffic have to do with fluid dynamics? Rather a lot, actually! Many parallels exist between traffic and compressible fluid flow. One such example, the concept of a shock wave, is demonstrated in the video above. As the traffic jam develops, the cars experience sudden changes in their velocity and relative distance (in a…
Volcanic Vortices
The volcanoes of the South Sandwich Islands, located in the South Atlantic, have a notable effect on cloud formation in this satellite photo. Visokoi Island, on the right, sheds a wake of large vortices that distort the cloud layer above it. On the left, Zavodovski Island’s volcano does the same, with the added effect of…
New CPU Fan
This video discusses a new quieter and more efficient CPU fan developed by engineers at Sandia National Labs. As the impeller spins, it draws ambient air down the center of the impeller while the shape of the fins forces air past the fins and out radially. As the air flows over the fins, it draws…
Schlieren Montage
Dr. Gary Settles, a world-reknown expert in schlieren photography, shows here a montage of some of his lab’s results, including shockwaves from musical instruments, dogs sniffing, guns firing (both sub- and supersonic), and even snapping a wet towel going supersonic. As Settles jokes, schlieren is all mirrors and hot air. Mirrors are used to shine collimated…