I noticed when swimming, I could breathe out and rise at the exact same speed as my bubbles. I could even breathe in and out! I've been thinking of this for days, but for a fun carnival ride, you could build a submarine without a hull!

It starts at the bottom of a tube of water, with a cler plastic hull around you and the air. The vehicle is relesed, and starts rising. The hull then retracts, and you are in a bubble! Small propellors on the vehicle ensure that you stay inside the bubble, and there are emergency bubble tanks that can add air to the bubble of some air splits off. Also air masks.

You rise at the same speed as the bubble, nd the air pressure keeps the water from collapsing onto you, enabling you to breathe safely, without a hull.

There may be initial problems perfecting the technique, but imagine what fun! Rising upwards inside of a giant bubble!
-- DesertFox, Jun 15 2005

Antibubbles http://www.antibubble.org/
maybe make a really big one, and have everyone just live in the little airspace, and float around in it! [daseva, Jun 15 2005]

Sounds like the best ride I can imagine.
-- reensure, Jun 15 2005


Did you mean diving in the first sentence, and can we review the breathe in part?
-- theircompetitor, Jun 15 2005


(+) Don't have the beans for lunch.
-- 2 fries shy of a happy meal, Jun 15 2005


//I could even breathe in and out// But not whilst watching your bubbles rise, I guess.
//but imagine what fun// Until someone forgets not to hold their breath. Bone.
-- coprocephalous, Jun 15 2005


You misunderstand.

You start at the bottom, with a hull around you. It retracts and you rise with the giant bubble, inside of the bubble. So you can breathe.

////I could even breathe in and out// But not whilst watching your bubbles rise, I guess. //

Um one large bubble around my mouth let me breathe, and other smaller bubbles around me I watch while floating upwards. I do it all the time in my pool.

////but imagine what fun// Until someone forgets not to hold their breath. Bone.//

You sort of missed the part about you being inside of a giant bubble, which just so happens to be the entire point of the idea.

I added the last line for a bit of clarity.
-- DesertFox, Jun 15 2005


[DF] The air your passengers breathe at the bottom of the ride will be at the same pressure as the water pressure at that depth. As the bubble rises, it will expand (you'll have observed that in your pool), as will the air in the passengers' lungs. If they hold their breath, that air will expand also, resulting in a lung over-expansion injury. Hope you've got good public liability insurance.
[sfb] forgot to mention the possibility of the bends too - depends on how long the riders are breathing compressed air.
-- TolpuddleSartre, Jun 15 2005


The passengers dont hold their breath. They breathe normally. Why would they hold their breath?
-- DesertFox, Jun 15 2005


//You sort of missed the part about you being inside of a giant bubble, which just so happens to be the entire point of the idea.\\ That made me smile.

But seriously, a bubble under water can only be so big right?
-- zeno, Jun 15 2005


Bun if it worked. BUt.....(1) You wouldn't be very much inside the bubble. If it were a big bubble, then you would (at best) have just your head in it, just as if you were floating on the top of the pool.

(2) I think that, even then, a big bubble would 'get away from you' and float up much faster than you would. The reason that small-ish bubbles rise more slowly is that their lift is small compared to the drag from water resistance. As the bubble gets bigger, the lift will increase much more than the drag, and the bubble will rise faster.
(3) I'm not sure, but I don't think a bubble that big would be stable - it would do something very odd like breaking up, or (more likely) collapsing into a toroid (basically, water from above the 'ceiling' of the bubble falls inward, filling the central column and leaving only a ring of air around it).
So, alas, I'm pretty sure it wouldn't work, so no bun after all.
-- Basepair, Jun 15 2005


“Ladies and gentlemen,” says Desert Fox, who is new to the Halfbaked Theme Park, and has completely misunderstood everything, “in this ride you can breathe underwater!”
Later, observing the pool, Jutta scowls. “DF, are those bodies I see?”
“Yes ma’am,” says DF, “they’re floating.”
“I can see THAT, but are they breathing?”
“Oh yes! They're breathing underwater!”
-- ldischler, Jun 15 2005


yes, big bubble will break. Water makes film at the air/water interface. Air pressure equals water pressure for very small bubbles. Big bibbles break from water pressure, forming smaller bubbles where the forces are well balanced.

Make an antibubble waterpark and watch the money flow, yeah!
-- daseva, Jun 15 2005


Won't work - you will fall out of the bubble.

You'll only rise if you're in water because of your buoyancy. Once you're even mostly surrounded by air, you'll stop rising.
-- waugsqueke, Jun 15 2005


//Why would they hold their breath// Because it is a common human reflex when surrounded by water.
-- coprocephalous, Jun 16 2005


I agree with Waugs. You rise at the same sort of speed as the bubble because you're both suspended in water. If you were inside of the bubble, your weight would pull you out of the bottom of the bubble.

Put someone underwater, even in a bubble, and they _will_ hold their breath. It may not make sense but it's the sort of thing that happens more or less by reflex in such situations.

Also I'm with zeno - big bubbles become unstable and break down into many smaller bubbles.

Finally, did you know that below a certain depth, the compression of your lungs means that you actually become more dense than water? At this depth (one of our diving 'bakers [normzone?] might enlighten us as to how far down this actually is) you will sink, while the bubble will rise.
-- david_scothern, Jun 16 2005


[ds] The lung compression thing only occurs with free-divers where you take your breathe at the surface - if you're in the bubble, then you'll breathe the air at ambient pressure, and your lungs maintain their normal volume. However, for scuba divers to avoid the bends, the maximum ascent rate is recommended as no more than 18m/minute, or about the same speed or slower than your smallest bubbles.
Experienced divers can blow bubble rings with surprising structural integrity, so maybe what is needed is some kind of submarine air-zooka.
-- AbsintheWithoutLeave, Jun 16 2005


no, if you take your breath underwater the air you breath will be at the same pressure as the surrounding water, thus the lung expansion injury mentioned earlier.

which is a shame, because i really like this idea
-- daaisy, Apr 06 2006


I think I have the solution to the pressure issue:
Put the entire pool in a low gravity environment. This has the additional advantage that your rise through the water will be that much slower.

How to do this? Well, apart from building it on the moon, you could drop the whole pool assembly at, say, 7.8 ms^-2. This would reduce the pressure per metre by about four-fifths.
The bubble carrying platform would drop slightly more slowly, to match the bubbles rise through the liquid.

The other thing to do would be to let air out of the bubble during its relative ascent, to maintain constant bubble size.

Finally, we probably only need a few seconds of bubble immersion. Since the hull is clear plastic, it could probably be arranged to be hard to notice as it retracted. So you set off on a long drawn out underwater jaunt in a submarine, then burst out of the water in a bubble. Obviously you'd get splashed, and might wonder how long you'd been loose.
-- Loris, Apr 06 2006


//you could drop the whole pool assembly at, say, 7.8 m/s // sp. "7.8 m/s^2"
-- coprocephalous, Apr 06 2006


Oh yeah. corrected.
-- Loris, Apr 06 2006


[loris], regarding the bubble in a low gravity environment, John Varley's "Blue Champagne" is a great read. One of the protagonists is a lifeguard in such a place.
-- normzone, Apr 06 2006


John Varley, I've read a few of his. They were good.
-- DesertFox, Apr 07 2006



random, halfbakery