In marbling, an artist floats paints on a viscosified water bath, using various thin tools to manipulate the final image. Many cultures have developed a version of this art, but Keep reading
Tag: low Reynolds number flow
Ciliary Pathlines
For tiny creatures, swimming through water requires techniques very different than ours. Many, like this sea urchin larva, use hair-like cilia that they beat to push fluid near their bodies. Keep reading
Featherwings in Flight
The featherwing beetle is tiny, less than half a millimeter in length. At that scale, flying is a challenge, with air’s viscosity dominating the forces the insect must overcome. The Keep reading
Falling Pancake Drops
Despite their round appearance, the droplets you see here are actually shaped like little pancakes. They’re sandwiched inside a Hele-Shaw cell, essentially two plates with a viscous fluid between them. Keep reading
Artificial Microswimmers
Tiny organisms swim through a world much more viscous than ours. To do so, they swim asymmetrically, often using wave-like motions of tiny, hair-like cilia along their bodies. Mimicking this Keep reading
The Challenges of Being Small
For juvenile fish, feeding is a challenge. Their small size — often less than 5 mm in length — makes hydrodynamically capturing prey much harder because of viscosity’s relatively larger Keep reading
The Microscopic Ocean
When you’re the size of plankton, water may as well be molasses. Viscosity rules at these scales, and swimming plankton leave distinctive wakes that are slow to dissipate. Fish that feed on plankton use Keep reading
Escaping the Limits of Viscosity
For large creatures, it’s not hard to feel the evidence of someone else swimming nearby. But to tiny swimmers water is incredibly viscous and hard to move. These creatures have Keep reading
Communication Between Microswimmers
The elongated cells of Spirostomum ambiguum swim using hair-like cilia, but when threatened, the cells contract violently, sending out long-range hydrodynamic waves, like those visualized above. Along with these waves, the Keep reading
Magma Mixing
Magmas typically consist of a mixture of molten liquid, bubbles, and solid crystals. As they mix, those crystals can sink from one viscous layer into another. To investigate this sort Keep reading