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Could somebody explain this strange video showing a "frozen" jet of water ? Or might it be a fake ? (I wasn't able to source it; no idea what 'CRCN' stands for).

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  • $\begingroup$ There is no indication of what the conditions are in the video. ie What is inside the blue tank? What is the temperature of the water? What is the ambient temperature? Is there anything mixed into the water? Without such information it is difficult to offer an explanation. Can water freeze so quickly? Yes, but usually it is in small droplets - for example in this video. $\endgroup$ Oct 7 '16 at 22:22
  • $\begingroup$ c.r.n.cs lead to a video upload site, gfycat.com which has a lot of altered / fancy cgi effects on it, so.......... my money is on a good hoax, running water through an outer frozen shell that does not seem to make physical sense. $\endgroup$
    – user108787
    Oct 7 '16 at 22:29
  • $\begingroup$ I'm suspicious of the way it always pans away quickly from what's going on on the ground. $\endgroup$
    – Gert
    Oct 7 '16 at 22:30
  • $\begingroup$ If it is a fake it looks very convincing. I don't see anything wrong with panning to the ground to show that the end of the stream is liquid. $\endgroup$ Oct 7 '16 at 22:40
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    $\begingroup$ The water isn't frozen, google "laminar flow". This article gives a more in-depth explanation: sciencealert.com/… $\endgroup$
    – Graumagier
    Oct 8 '16 at 8:14
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According to sciencealert.com the phenomenon responsible for the "frozen" stream of water is laminar flow, characterized by layers of fluid moving basically in parallel to each other, with very little cross-currents or turbulence. While that still does not definitively prove that the video wasn't faked (can't prove a negative) it provides a (IMO plausible) mechanism for what the video shows. There are other videos on YouTube that show pretty much the same thing. For reference, here's the Reddit thread where the GIF was originally posted.

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  • $\begingroup$ As a child I spent a long time playing with taps, and, if you adjust things just right (and have the right tap), you can get a flow from a tap which, for maybe 5cm or more, looks like it is solid. I think this must be laminar flow, and this video demonstrates a mire impressive version of the same thing. $\endgroup$
    – user107153
    Oct 8 '16 at 21:14
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    $\begingroup$ The thing that prevents me to be totally convinced is that the small capillary details are totally stable as well. Even the reflects and light caustics are totally stable (which is quite extreme), despite potential capillary instabilities, air friction, etc. The extra videos are cool, but they concentrate on "fiber glass look", or show some small instabilities. At least they (or others similar) detail technically why and how to avoid interaction on the surface, by having the narrow part of the nozzle as thin as possible to avoid friction. $\endgroup$ Oct 9 '16 at 7:52
  • $\begingroup$ ... (still, to me this avoid shear and thus turbulence, but not capillary excitation. But it might at least prevent their initial instability). Seems like maybe my love for capillary waves is just not universal. :-) A few more: youtube.com/watch?v=RvReD5Xyjo4 , youtube.com/watch?v=VKkQan82ukI , youtube.com/watch?v=rscpnV5DBSo . $\endgroup$ Oct 9 '16 at 7:53
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Here is a video explaining this effect:

https://www.youtube.com/watch?v=uZh8Dfymg38

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    $\begingroup$ Link-only answers should be avoided. Try to summarise the answer in the post itself. $\endgroup$
    – ahemmetter
    Oct 8 '16 at 21:14
  • $\begingroup$ Links are perfect for me, at least in some cases like here. Cool ! $\endgroup$ Oct 9 '16 at 7:54
  • $\begingroup$ Kind of like a screen on steroids. $\endgroup$ Oct 12 '16 at 0:41
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I have dealt with fluid extensively used as "mud" to pick up cuttings in well bores for drilling for oil and gas. It's a little more complicated than that and all kinds of liquids are used down to just plain water. It was done with all kinds of mixing applications and in all kinds of temperatures with extensive testing and visualizations of these fluids characteristics. If the hole in this video had a screen in it used as a filter of sorts and possibly even coned shaped or even if not and if cold enough it is very possible. With the break in the total column of water with a thin indistinguishable spray or layer at the outside would make it very possible if not probable. This effect would only allow it to happen for a short distance as mixing would eventually happen. As stated there is not enough information but taking this liberty of speculation makes it doable.

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