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Researchers Discover That Sand Behaves Like Water

Posted by Soulskill on from the not-in-your-stomach dept.

Xeger writes "University of Chicago researchers have found that streams of sand can behave in a similar manner to liquids, forming water-like droplets when poured from a funnel. To obtain these results, they dropped their expensive high-speed camera from a height of several meters and observed the sand forming into droplets — something that shouldn't happen without surface tension. These findings suggest that conventional engineering wisdom about sand, dirt and other grainy materials needs to be rethought, and that it might be possible to apply fluid dynamics to some solids problems."

7 of 192 comments (clear)

  1. Pour sand in a vacuum by Baldrson · · Score: 1, Redundant
    The video shows sand droplets forming but some of the smaller droplets are falling more slowly than the larger droplets. This indicates the drop column has air in it.

    Evacuate and try it again...

    --
    Seastead this.
  2. What about the air? by White+Flame · · Score: 0, Redundant

    As sand falls, it would push air molecules around, causing minor pockets of slightly higher & lower air pressure. I have no clue what sort of contribution that would be, and expect to be schooled by people much more informed in this matter than myself in the subsequent replies.

    1. Re:What about the air? by Timmmm · · Score: 0, Redundant

      Air gets my vote too. It would be interesting if they could do the experiment again in a vacuum.

  3. Re:hmm... by MouseR · · Score: 0, Redundant

    I'd like to see that in a vacuum.

  4. This is news by Hognoxious · · Score: 0, Redundant

    I knew some guys who were studying this when I was an undergrad, and it wasn't new then: http://en.wikipedia.org/wiki/Fluidized_bed

    --
    Confucius say, "Find worm in apple - bad. Find half a worm - worse."
  5. What about in vacuum? by argent · · Score: 0, Redundant

    Do the same effects occur in a vacuum?

  6. Re:hmm... by Livius · · Score: 0, Redundant

    Clearly some of the air will be accelerated and it's pressure will change. They will have to try it in a vacuum.