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Avalanches Simulated With 500,000 Ping-Pong Balls
An anonymous reader submits "Ping-pong ball avalanche experiments have been carried out for the last three years at the Miyanomori ski jump in Sapporo, Japan, to study three-dimensional granular flows. Up to 550,000 balls were released near the top of the landing slope. The balls then flowed past video cameras positioned close to the flow, which measured individual ball velocities in three dimensions, and air pressure tubes at different heights. The flows developed a complicated three-dimensional structure with a distinct head and tail, lobes and 'eyes.' See for yourself, it's quite interesting!"
"Hey Bill, we've got tons of ping-pong balls and a very elaborate and sophisticated means of tracking their movement - what should we do with them?"
"Uhh, use them to predict the Powerball results and retire on private carribean islands, unique ones of which we own for every day of the month?"
"No, you fool! Avalanche research is clearly the way!"
The only tragic victim of this experiment was this man.
A bespecticled bunny rabbit and moose were seen running from the scene.
It is easier to build strong children than to repair broken men. -Frederick Douglass
Yeah, you figure if he's curious enough to take the time to post "why?" he'd be curious enough to CTFL! (Click the fucking link).
Anyway, clicking around the site, this prime example of what it's all about:
My current research is concerned with the dynamics of avalanches. Avalanches are sometimes treated as a special sort of granular flow. These have been studied for a long time but because they can have solids, fluid and gaseous properties satisfactory theories do not exist except in special situations. An excellent starting point is Taguchi's Powder Page. To understand these flows better a series of experiments was started last year of ping-pong ball avalanches on a ski jump in the outskirts of Sapporo. Up to 300,000 ping-pong balls were released from the top of the landing slope and their subsequent motion analyzed using video cameras. These flows are a much simpler than real avalanches but they do have similarities and any model that cannot explain these flows will certainly fail on real avalanches. I am developing a model to predict these kind of flows.
I hate ping pong avalanches.
The hardest part is digging yourself out with nothing but a ping pong paddle...
"Can of worms? The can is open... the worms are everywhere."
This is an interesting experiment and all, but it resembles a real avalanche about as much as computer climate models resemble real weather.
A actual avalanche is orders of magnitude more complicated. It'd probably be easier, and much more informative, to simulate it on a computer, actually.
It does make for some good eye candy, tho, and I'd bet it was a whole lot of fun. As a serious scientific tool, it's probably not very effective in this day and age, given the better tools out there.
As a teaching tool, however, it has astounding potential, especially in primary education.
Just as an aside, I've witnessed a few large avalanches. I was fascinated (and horrified) at the time; the fascination came from observing the complex flows introduced by various things such as the underlying terrain, trees, assorted rocks, etc. I remember thinking the last time that it was a good demonstration of fluid flow dynamics. The horror came from watching several skiers get caught up in the snow flow. They survived, thank Guh.
(Disclaimer: IANAMathematician).
SB
It's old. The more humans I meet, the more I like my cats. At least they are honest.
I went to the Open House for the mining engineering program at my university (Queen's) and one of the professors showed us how they use computer simulations to model rock interactions. The simulations modelled the behaviour and interactions of thousands of sample rock particles. Really interesting stuff. I guess this kind of test is where they get the raw data to develop these computer models.
Mining engineering is also cool because there is a required explosives and blasting course in second year.
boom boom boom
But my coffeepot does talk to me!
I am one of many. My idea is not unique, nor do I expect my voice alone to sway you. I speak in a chorus of opinion.
This is pretty cool, sort of an "avalanche light" experience.
They could rescue people with chihuahuas carrying cans of diet pepsi.
Cole's Law: Thinly sliced cabbage
Maybe this means we can use badgers to predict avalanches! =)
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I remember running across references to this research before; apparently, the research staff, as part of a press conference, decided to stand on the slope when they dumped the ping-pong balls to give the photographers some dramatic photographs. After all, they were just ping-pong balls, right? Too light to do anything, right? Well, if you look at the image sequence one,two, and three, you'll see that the researchers discovered that while one ping-pong ball has a trivial impact, half a million of them is another thing entirely, knocking people off their feet.