Extruding Ice from Steel Fences and Pipes with Diurnal Freeze/Thaw (2008) | Hacker News Reader

Extruding Ice from Steel Fences and Pipes with Diurnal Freeze/Thaw (2008)

my.ilstu.edu

261 pointsyosamino21 comments

Pretty cool. I don't ever remember seeing this occur anywhere. More examples of this occurring in nature on his main page: http://my.ilstu.edu/~jrcarter/ice/diurnal/

Yeah I seen the on a BBC winter watch program. The trees needed a fungus for it to happen in the UK

Similar growth patterns occur in calcite https://en.wikipedia.org/wiki/Helictite but the effort of reproducing and documenting with water ice is impressive, and much more reproducible.

Somewhat related is needle ice[1] and ice wool. Temp and humidity differences cause curious ice formations.

[1] https://en.m.wikipedia.org/wiki/Needle_ice

Ice wool needs a specific fungus as a catalyst to grow: https://en.wikipedia.org/wiki/Hair_ice

Something similar happens in the New Jersey area around the forests (and I imagine other foresty places with cold weather) if you're hiking and you look down during some frosty days you can see ice being extruded from the ground in a way that looks like ice spaghetti. It was pretty neat the first time I saw it.

Eerily reminiscent of tin whisker formation.

https://www.youtube.com/watch?v=kYlWjqb-Qvg

Wondering if you could make winter ice fountain sculptures out of this phenomenon

This is reminiscent of these plants: http://www.greatstems.com/2013/12/beautiful-ice-sculptures-o...

anybody have a line on time-lapse video of this phenomenon?

Yes: https://www.youtube.com/watch?v=nbiEfr5FxEA

3D printing for water(ice)?

Reminds me of "ice jacking" that was blamed when a ski lift collapsed in Whistler.

https://www.piquenewsmagazine.com/whistler-news/ice-jacking-...

Exotic beautiful cold desserts, anyone?

I wonder what would happen if you threw some motion on the pole. Make it spin around and see what patterns you get

A time lapse would be awesome!

This would be a delicious form of ice cream

Would be fun to try this with Bismuth.

To me this seems straightforward.

The expanding ice forces water to flow slowly out any region it can due to hydraulic pressure (no mystery here).

At cold temperatures the water flowing through a crack freezes, taking the shape of the hole it came out(again, no mystery here).

While it's beautiful, I'm not sure how this is news.

The author actually suggests different mechanism where not water but solid ice is pushed through the hole by the expansion behind it.

Because if purely liquid water seeps out, it will flow away. If it were cold enough to freeze it immediately, it would freeze the opening shut. There needs to be at least a slush to give enough structure to freeze onto, like an icicle.

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