Drops of ethanol on a heated surface contract and self-propel as they evaporate. My first thought upon seeing this was of Leidenfrost drops, but the surface is not nearly hot Keep reading
Tag: marangoni effect
Soapy Solutions
When a drop of soap falls into a pool of water, its surface-loving molecules spread out on the water’s surface. Exactly how the soap spreads depends on the local concentration Keep reading
“Titan”
Saturn’s moon Titan is a fascinating foil to our planet. It’s the only other body in our solar system with liquid bodies — lakes and seas — on its surface. Keep reading
“I See You”
In “I See You,” filmmaker Rus Khasanov captures fluid flows that give the screen an eye with which to gaze back at us. The textures visible in the flows are Keep reading
When Seeing a Flow Changes It
Adding dye to a flow is a common technique for visualization. After all, many flows in fluids like air and water are invisible to our bare eyes. But for some Keep reading
“Velocity”
In this short film by Vadim Sherbakov, macro shots of glittery ink and pigments look like astronomical vistas. The title of the film, “Velocity,” is spot on; every shot is Keep reading
“Heaven”
Wispy white cirrus clouds cover dark skies glittering with stars in Roman De Giuli’s “Heaven”. Or so it appears. In reality, these skyscapes are made with watercolors, ink, and acrylic Keep reading
When Bubbles Don’t Die
In a pure liquid, most bubbles pop almost immediately. But with a simple ingredient — a little heat — bubbles can live almost indefinitely. The mechanism is revealed in this Keep reading
“Delusion”
Soap films are ephemeral and ever-changing. The shifting concentration of surfactants along the surface of the film, combined with thermally-driven convection, keeps the fluid in motion. The shifting colors reflect Keep reading
Acrylic Paint Fractals
Here’s a simple fluids experiment you can try at home using acrylic paints, ink, isopropyl alcohol and a few other ingredients. When dropped onto diluted acrylic paint, a mixture of Keep reading