This video, created by undergraduates as part of a fluid dynamics laboratory course, shows flow visualization of a von Karman vortex street in the wake of a cylinder in comparison Keep reading
Month: September 2024
Tip Vortices
Like airplane wings, helicopter blades have tip vortices. In this photo, the air’s humidity was great enough that the acceleration caused by the passing of the blades caused a pressure Keep reading
Effects of Viscosity
[original media no longer available] Today’s video demonstrates the effect of viscosity, which measures a fluid’s resistance to deformation. On the left is a column of highly viscous fluid; the Keep reading
Zero-G Water Bubbles
Astronaut Don Pettit narrates some of his experiments with air and water droplets in microgravity in this video. The lack of body forces and buoyancy in microgravity means that surface Keep reading
Stirring with Electromagnetism
If a fluid is electrically conductive, then magnetohydrodynamics (often abbreviated as MHD) describe its behavior. Electric and magnetic fields can be used to stir such a fluid, as in the Keep reading
Water Balloon Photography
Photographer Edward Horsford uses high-speed photography to capture water balloons as they burst. On Earth, of course, gravity wins over surface tension, but the results are very different in microgravity. Keep reading
Wave Pool
This Japanese pool, lined with computer-controlled actuators, uses the principle of wave interference to create complex shapes at the center of the pool. While we may be more familiar with Keep reading
Three Flows in One
These plumes of smoke demonstrate the three types of fluid flow: laminar, transitional, and turbulent. At the bottom of the photo, the plumes are smooth and orderly, as is typical Keep reading
Seeing Shock Waves with Schlieren
Schlieren photography is actually a pretty commonly used system in high-speed experimental aerodynamics. A typical schlieren system will shine a collimated light source on the target (a wind tunnel test Keep reading
Convection in Cream and Liqueur
We are used to associating convection with differences in temperature, but what’s actually necessary for a Rayleigh-Taylor-type instability is a density variation (and a gravitational field). The solutal convection seen Keep reading