Regular self-similar pattern when ink dissolves in water

This is a demo of phenomenon that showed by J. J. Thomson more than one hundred years ago in
"On the Formation of Vortex Rings by Drops Falling into Liquids, and Some Allied Phenomena".
It was a big surprise to me when I saw it. A recent interesting paper on Nature Physics
called "Single-drop fragmentation determines size distribution of raindrops" that shows an amazing aspect of
similar phenomenon but in the case of raindrop.

Category:

Film & Animation

Tags:

• fluid
• self-similar
• instability

[pantelopes]

I would personally repeat the experiment with different solutions (water with various pHs, ethanol, oils, etc) and ideally different weighted inks (homemade dyes with various glucose/etc concentrations) and see what happens before looking for mathematical explanations. That's my perspective as a biologist, anyway ;)

[miaohaixing]

That would be great;-)

[Rubbleblock]

I'm no expert but here's an idea: the first vortex ring contracts into droplets by a PlateauRayleigh instability. This would explain why the 3-drop pattern consistently re-appear, something the random initialization of a RT-instability couldn't supply. The drops pick up speed (you can see the vertical acceleration in the trails) until the speed gets so high as to give turbulent flow. A vortex is then created, decelariting the ink. Droplets form from the vortex and the cycle is repeated.

[miaohaixing]

Yes, you could be right! It might be a combination of RT and PR instability. Basically, the drop first gets flattened. Due to RT instability, the water penetrates this ink plane and forms a torus. After the torus grows to some point, its surface tension breaks it into smaller droplets due to PR instability. This process repeats itself and forms this self-similar pattern.

[cuallito]

Cool! Is it just normal ink?

Does the water have to be super still?

[miaohaixing]

Just normal Parker ink. The water needs to be reasonably quiet not super though.

[benizc00L]

You guys are missing the point... there is totally a smiley face in the first layer at about 16 seconds.

[theonewhoisone]

SWEET JESUS

[kirchnersala3991]

@pantelopes Amazing Idea.. but i would add, different kinds of container shapes!

[SuperFantageVideos]

Cool

[0yaa]

Just like that.

[MasterHorschti]

Das habe ich mit meiner Kamera fotografiert

[paws27]

as the top comenets say i dont under stand but what i this there sating is ink make pretty paterns

[Firepath]

@CanWire I agree, it syncs up / agrees with chaos theory too.

[nelron095]

i find this video hard to masterbate to

[Hogger542]

now drink it!

[wesselbindt]

@CanWire

Schrödinger disagrees.

[Amberblaze223]

@joelito101 true that, but, again, mabey we're both right, or both wrong. We might never know what infinity really is. I still remember when i was little and i watched the PBS kids thing. "Captain Infinity" and all that.