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Mathematicians Show Why Bubbles Sink in Nitrogen-Infused Stouts
SicariusMan writes "The age old question: do Guinness and other stouts' bubbles really sink, or is it an optical illusion? Well, some mathematicians have figured it out."
Full paper via arXiv; From the article: "To analyze the effect of different glass shapes, the mathematicians modeled Guinness beer containing randomly distributed bubbles in both a pint glass and an anti-pint glass (i.e., an upside-down pint). An elongated swirling vortex forms in both glasses, but in the anti-pint glass the vortex rotates in the opposite direction, causing an upward flow of fluid and bubbles near the wall of the glass."
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Allow me to practice ...
Researchers learn to spell.
The Australians figured it out 12 years ago
http://science.slashdot.org/story/00/01/11/2156213/why-bubbles-in-guinness-fall
Twelve years ago an almost identical paper was on the office wall of a chemical engineering professor I had in college. I'm mostly kidding with my subject line - I expect there's novelty in the new paper and just want to point out that this has been used as a model system (probably many times) before now.
"I zero-index my hamsters" - Willtor (147206)
I believe this study will end up receiving more than its fair share of replication and confirmation studies.
In fact, I can see several follow-up studies on if (and possibly why) this is specific to stout. How about a nice lager "control group" for the lads at table 3?
Learning HOW to think is more important than learning WHAT to think.
Mythbusters (accidentally) did it first.
http://www.youtube.com/watch?v=q4YeP7e0tPE&t=190
That's an astout observation!
Hence, no stout for you, mister. ;)
I thought it was just a side effect of drinking the stuff.... Like the floor smacking me in the face... Hey, bar-keep! Keep'm coming until the bubbles start sinking...
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Australians do not like any confusion or doubt when it comes to beer. Mind you, apparently they initially thought it happened because Guiness comes from the North.
...I repeat DO NOT touch a pint glass and an anti-pint glass during a toast.
That is all.
I ran the experiment using an anti-stout glass but my results differed from the theory in original paper - instead of the bubbles rising, they ran all over the floor.
Guiness is brewed in Ireland. The bubbles are made in Australia. When the can is opened the bubbles attempt to to up, but they are from Australia so they head the wrong way. Another pint of your finest, barkeep!
Their answer is "because the math says so"?
just wants to be free*.
* Free as in information - uuuurrrrrp! ('scus me! And CO2).
in the anti-pint glass the vortex rotates in the opposite direction, causing an upward flow of fluid and bubbles near the wall of the glass
Just don't drink too many anti-pints of beer. I tried it once and woke up with a hell of a hangunder.
Big apple, new Yorik, undig it, something's unrotting in Edenmark.
in the anti-pint glass the vortex rotates in the opposite direction, causing an upward flow of fluid and bubbles near the wall of the glass
Just don't drink too many anti-pints of beer. I tried it once and woke up with a hell of a hangunder.
Hangin out on the Disc again? Bugarup. Millenium hand and shrimp, I says! :)
"I love animals! Some are cute, others are tasty, what's not to like?" - Betsy Schroeder, Jeopardy contestant
Come on.. Really? and they got someone to fund this beer research? Damn, those guys are smart!
and a dupe at that
At the end of the paper they tantalisingly open the door to the possibility that there might exist a glass which would allow Guinness to settle more quickly. If such a glass were discovered, Irish barmen (well, all barmen really) would be able to pull pints more quickly. This means that fewer barmen would be required to man a bar so barmen would lose their jobs, increasing unemployment and probably plunging the country (perhaps the world) further into recession. Risky research.