For this image, two artificial fish fins are placed side-by-side and flapped in phase. Flow in the image is upward. The wakes of the fins interact in a complicated vortex Keep reading
Month: January 2025
Ultrasonic Levitation of Drops
This video shows an ultrasonically levitated 3 mm drop of propylene glycol changing shape. A couple of things are happening here. Firstly, the drop is suspended due to the acoustic Keep reading
Oceanic Swirls
Mixing of surface waters with deeper ocean currents brings together the minerals and nutrients used by phytoplankton, resulting in gorgeous swirls of color in the ocean. These phytoplankton blooms are Keep reading
Dove in Flight
This spectacular high-speed video shows a dove in flight. Note how its wings flex through its stroke and the way the wings rotate over the course of the downstroke and Keep reading
Inside a Blender
[original media no longer available] High-speed video visualizes the complicated flow field inside a blender. Note that the video is placed in reverse for artistic effect. This flowfield is clearly Keep reading
The Invisible Forces Behind a Lighter
This high-speed schlieren video reveals the ignition of a butane lighter. The schlieren optical technique exaggerates differences in refractive index caused by density variations, enabling experimentalists to see thermal eddies, Keep reading
Cloud Streets from Space
Cloud streets flowing south across Bristol Bay hit the Shishaldin and Pavlof volcanoes, which part the air flow into distinctive swirls called von Karman vortex streets. As air flows around Keep reading
Staining Patterns
This timelapse video shows a particulate suspension as it dries and the pattern formation that results. The mixture of silicon dioxide particles and water is spread over a glass slide. Keep reading
Worthington Jet
A drop of sugar syrup falls into a pool of methylated spirits, producing a Worthington jet and several ejected droplets. Although surface tension holds the jet in a smooth shape, the Keep reading
Sloshing to Dampen
In this high-speed video, two flexible spheres are dropped from the same height. The one on the left is filled with air, the other is partially filled with a liquid. Keep reading