The winds of Mars create sand dunes that seem to flow like a liquid across the planet’s surface. Here the wind blows from right to left around the flat top Keep reading
Month: December 2023
Helicopter Vortices
When conditions are just right, the low pressure at the center of a wingtip vortex can drop the local temperature below the dew point, causing condensation to form. Here vortices Keep reading
Convective Cells
Convective cells form as fluid is heated from below. As the fluid near the bottom warms, its density decreases and buoyancy causes it to rise while cooler fluid descends to Keep reading
Supercritical Fluids
A supercritical fluid exists without a distinct liquid or gas phase and forms when temperatures and pressures exceed the substance’s critical point. Here supercritical transition is demonstrated with an ampule of liquid Keep reading
Supercavitating Penguins
[original media no longer available] Penguins, already fluid dynamicists by nature, have developed clever methods of increasing their speed to escape from the leopard seals that prey on them. In Keep reading
Reader Question: Fire as a Fluid?
Reader David L asks: I understand that fire is a form of energy rather than a fluid in the physical/tangible sense. However, is it possible for fire to exhibit fluid-like Keep reading
Bursting Bubbles
Sometimes bursting one bubble just leads to more bubbles. This high-speed video shows how popping a bubble sitting on a fluid surface can lead to a ring of daughter bubbles. Keep reading
F-18 Flow Viz
Water tunnels are useful tools for determining aerodynamic characteristics of aircraft, such as this F-18 model placed in the NASA Dryden Flow Visualization Facility. By matching the Reynolds number of Keep reading
“Ferroux”
In this video, artist Afiq Omar mixes ferrofluid with soap, alcohol, milk, and other liquids to create a surrealistic fluidic dance. In addition to using different fluid mixtures, I suspect Keep reading
Flapping to Fly Efficiently
High-speed video shows that bats achieve some of their efficiency in flight by pulling their wings inward on the upstroke, as seen above. While this does affect drag forces on Keep reading