Beta
×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

Future Ships Could Float On Bubbles

kdawson posted more than 7 years ago | from the always-knew-champagne-eases-friction dept.

Power 314

MattSparkes writes, "Creating a layer of bubbles underneath a ship's hull could improve fuel efficiency by 20%. When you consider that 90% of the world's goods are transported by sea, the importance of this discovery is obvious. 'Conjured up from thin air at the flick of a switch, this slippery blanket will help transport a fully laden tanker or container ship across the ocean at higher speed, and using far less fuel, than ever before... There is currently no other technique in naval architecture that can promise such savings.'" The article looks in some detail at the engineering problems that will need to be overcome before this technique is practical.

cancel ×

314 comments

Sorry! There are no comments related to the filter you selected.

other options (4, Funny)

User 956 (568564) | more than 7 years ago | (#17007364)

Creating a layer of bubbles underneath a ship's hull could improve fuel efficiency by 20%

But have they tried rainbows and/or fairie dust?

Re:other options (2, Funny)

Marxist Hacker 42 (638312) | more than 7 years ago | (#17007612)

I was thinking Air Hockey tables. I mean, the tech to do this isn't exactly rocket science, it's more like Disco Science. I think these Japanese Ship Builders probably have an unhealthy obsession with Olivia Newton John...

Re:other options (0)

Anonymous Coward | more than 7 years ago | (#17007668)

How about sending all material goods through cavitating torpedos? What could go wrong?

Re:other options (2, Funny)

pilgrim23 (716938) | more than 7 years ago | (#17007766)

Lawrence Welk where are you now that we need you?

Re:other options (0, Troll)

proxy318 (944196) | more than 7 years ago | (#17007912)

I've heard they've had good results with unicorn farts.

Hot Air (1)

vivin (671928) | more than 7 years ago | (#17007920)

This sounds like a lot of Hot Air! Pshh...

But how will it affect buoyancy? (5, Interesting)

with_him (815684) | more than 7 years ago | (#17007386)

Since methane hydrates releases are still suspected in the sinking of ships, how do the researchers account for the loss of buoyancy? Since this research calls for redesign of current ship building know-how, how are they planning on addressing the buoyancy part of the equation? To read more check out this http://www.newscientist.com/article.ns?id=dn1350 [newscientist.com] and http://jbj.wordherders.net/archives/000992.html [wordherders.net] someone trying to weaponize the buoyancy concept. http://www.nexusresearchgroup.com/fun_science/buoy ant1.htm [nexusresearchgroup.com] A fun science experiment for the kiddies, or others that want to understand it better.

Re:But how will it affect buoyancy? (0)

Anonymous Coward | more than 7 years ago | (#17007494)

re: weaponizing. Just thought I'd jump in and mention that this principle is used in the launching of missiles from submarines. Turns out that pushing a missile though water is hard, but if you put it in a gas bubble it's alot easier. Gas bubbles have very little friction against the water for some reason.

I Didnt RTFA, but I assume its the same principle.

Re:But how will it affect buoyancy? (2, Insightful)

jigjigga (903943) | more than 7 years ago | (#17007626)

good point, i was going to bring this up in my post. I bet the bubbles add a little instability from side to side as that is where the most give would be, but none from the bottom (thats why there will be no bubbling along the bottom of the hull);

Re:But how will it affect buoyancy? (2, Interesting)

DilbertLand (863654) | more than 7 years ago | (#17007674)

With methan hydrate releases the theory is that the entire volume of water surrounding the ship is "full of bubbles" and has an effectively lower density. What they are talking about here us just surrounding the hull with a thin layer of bubbles.....maybe the ship sits a couple inches (to pull a guess out of my rear) lower in the water....but there's not going to be any danger of sinking a ship...

Re:But how will it affect buoyancy? (0)

Anonymous Coward | more than 7 years ago | (#17008018)

Well, OK, but if there is a thin layer of bubbles surrounding the hull, then from the hull's perspective, the surrounding water is "full of bubbles", so the ship sinks down an inch where it is once again supported by solid water ... but that pulls the bubble machine down an inch lower, and so, once again the water surrounding the ship is "full of bubbles, and it sinks down another inch...

Now, if the bubbles were introduced just in the front, and not along the bottom, I could see some advantage. The water that the ship has to push through to move ahead is less dense than regular water, but the water under the bottom is still solid. However, since "front" and "bottom" overlap in a ship (and since some of the bubbles introduced in the front will pass along the entire length of the hull), it would seem that doing this without making the ship unstable would be a tricky thing.

Maybe a system that could be used in good conditions but would have to be shut down whenever wind or wave reached some threshold would be managable.

Re:But how will it affect buoyancy? (0)

Anonymous Coward | more than 7 years ago | (#17008176)

After the ship sinks down an inch it is supported by compressed bubbles, not solid water.

Re:But how will it affect buoyancy? (0)

Anonymous Coward | more than 7 years ago | (#17008258)

After the ship sinks down an inch it is supported by compressed bubbles, not solid water.

I hope so, because ships and solid water don't mix! [titanic.com]

Re:But how will it affect buoyancy? (-1, Troll)

Anonymous Coward | more than 7 years ago | (#17007882)

Hey, I discovered that when I was 4 years old when I farted in the bathtub and my rubber ducky sank... I cried.

Re:But how will it affect buoyancy? (1)

rucs_hack (784150) | more than 7 years ago | (#17008160)

those are releases on a vast scale, so much so that the ship no longer has sufficient mass of water around it to stay on the surface, and it lowers to its new level, which is far too low under the surface for survival. I don't think it's the same thing at all.

The same concentration reaches up into the sky and causes planes to go boom impressively it is beleived. The hypothesis being that the reduced density of the water causes the fragments to also sink below the surface instantly, which is why there is no surface debris to find, even potentially floaty bits.

This finding should have put paid to the whole 'aliens stole the ships/planes' thing, but that hasn't happened for some reason. Probably because the people who make a living expounding the alien myth have too much revenue to lose.

Praire/Masker? (1, Informative)

Anonymous Coward | more than 7 years ago | (#17007394)

I thought putting millions of bubbles around a ship was a good way to hide it from SONAR?

Re:Praire/Masker? (2, Informative)

n0dna (939092) | more than 7 years ago | (#17007632)

It is a good way to hide something, except of course that a huge unaccounted for cloud of bubbles is fairly unusual, especially if it's steaming towards King's Bay Georgia at 15 knots.

Re:Praire/Masker? (0)

q-the-impaler (708563) | more than 7 years ago | (#17007938)

I use millions of methane bubbles to repel humans in the pool.

Just skipping along. (0)

Anonymous Coward | more than 7 years ago | (#17007418)

"There is currently no other technique in naval architecture that can promise such savings.'""

Hovercraft. Ground-effect seaplanes. Boats that use skis.

Re:Just skipping along. (1)

frosty_tsm (933163) | more than 7 years ago | (#17007486)

Or how about not shaping the hull like a giant parachute. We are already putting that one to good use.

Re:Just skipping along. (1)

Volante3192 (953645) | more than 7 years ago | (#17007552)

Call me crazy but I don't think you can make an aircraft carrier that runs on skis. Or an oil tanker. Or the QM2.

He who lays bubbles? (2, Funny)

frieza79 (947618) | more than 7 years ago | (#17007434)

Layer of Bubbles? How can Michael Jackson decrease fuel consumption.

Re:He who lays bubbles? (0)

Anonymous Coward | more than 7 years ago | (#17007492)

And who will be blowing these so called "Bubbles"?

Re:He who lays bubbles? (1)

jpardey (569633) | more than 7 years ago | (#17007744)

Ah yes, a "Michael Jackson has sex with children" joke. Funny!

Re:He who lays bubbles? (1)

iamdrscience (541136) | more than 7 years ago | (#17007784)

Actually it was a "Michael Jackson has sex with monkeys" joke, which is rather novel by comparison.

Re:He who lays bubbles? (1)

jpardey (569633) | more than 7 years ago | (#17008200)

Oh wait, that South Park episode had confused me. Still, taking the basic pot shot at Whacko Jacko and extending it to a chimp, classy!

Re:He who lays bubbles? (0)

Anonymous Coward | more than 7 years ago | (#17008168)

I (for one) can't wait for the next "Is that you, Michael Richards?" joke! Ah, American humour!

Beans (0)

Anonymous Coward | more than 7 years ago | (#17007444)

That's how I float in the tub!

The wife wanted a spa and I'm just doing my part for energy efficiency.

The technique sounds like a lot of hot air (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#17007450)

I bet this blows for sea transport.

Offshoot of supercavitation? (1)

jigjigga (903943) | more than 7 years ago | (#17007452)

Sounds a little like supercavitated torpedoes, where the bubbles minimize drag except in this case they aren't encasing the ship in air. What ever happened to supercavitation anyway? Was it actually ever used or extended beyond torpedoes?

Re:Offshoot of supercavitation? (1)

Broken scope (973885) | more than 7 years ago | (#17007498)

Its still there, they just need to work out some more kinks... I know its not dead.

Re:Offshoot of supercavitation? (2, Informative)

with_him (815684) | more than 7 years ago | (#17007522)

Sounds a little like supercavitated torpedoes, where the bubbles minimize drag except in this case they aren't encasing the ship in air. What ever happened to supercavitation anyway? Was it actually ever used or extended beyond torpedoes?
Yes and in the article they talk about that a little bit near the end.
The idea of air cavities has much in common with supercavitation, in which a submerged object such as a torpedo creates a single large bubble around itself. This slashes skin friction, bringing remarkable speeds within reach (New Scientist, 22 July 2000, p 26). Perhaps not surprisingly, Russian engineers who first developed supercavitating torpedoes have not only done plenty of research on air-cavity lubrication for ships, but have also put their ideas to work.

Re:Offshoot of supercavitation? (1)

jandrese (485) | more than 7 years ago | (#17008082)

I think supercatavation only works if you're moving rather quickly through the water, so torpedoes are just about the only thing it makes sense on.

Have they factored in.... (0)

CastrTroy (595695) | more than 7 years ago | (#17007456)

Have they factored in the amount of energy required to create the layer of bubbles?Seems like creating a layer of bubbles around the hull of a giant ship would take quite a bit of energy.

Re:Have they factored in.... (0)

Anonymous Coward | more than 7 years ago | (#17007520)

Just feed all the sailors beans and let them loose. Bubbles a plenty!

Re:Have they factored in.... (5, Informative)

Daniel_Staal (609844) | more than 7 years ago | (#17007644)

Have they factored in the amount of energy required to create the layer of bubbles? Seems like creating a layer of bubbles around the hull of a giant ship would take quite a bit of energy.
They are moderately intellegent people. They do think of these obvious things...

(For reference: It is a major problem for one of the approaches being researched, but only one. Another approach already has a 40% reduction in friction by diverting 3% of the ship's power. Well worth the expendeture.)

Re:Have they factored in.... (1)

nick_davison (217681) | more than 7 years ago | (#17007896)

Yes: It turns out that, over time, they believe they can get it down to needing no more than 21% of the fuel a ship currently requires.

Don't some military ships use this? (1)

EvilMonkeySlayer (826044) | more than 7 years ago | (#17007458)

The theory being that the air bubbles help reduce the noise hence they're more silent to passive sonar systems on submarines, useful for anti-submarine warfare.
Or did I read it in a Tom Clancy book? Probably a little from column a and a little from column b.

Re:Don't some military ships use this? (1)

T-Ranger (10520) | more than 7 years ago | (#17007736)

Most likely neither. Bubbles are loud. Bubbles are bad. http://en.wikipedia.org/wiki/Cavitation [wikipedia.org]

Re:Don't some military ships use this? (0)

Anonymous Coward | more than 7 years ago | (#17007864)

If you read Tom Clancy's The Hunt For Red October, you will see that cavitation(aka bubbles with its "revolutionary" design) is the main reason why Red October was found. Bubbles are made up of airs (duh), therefore they reflect/refract sound wave differently.

Re:Don't some military ships use this? (4, Funny)

drinkypoo (153816) | more than 7 years ago | (#17007900)

Uh, creating bubbles by cavitation is entirely different, happens for an entirely different reason, and has nothing whatsoever to do with this. YOU WIN TEH PRIZE!

Re:Don't some military ships use this? (3, Informative)

Daniel_Staal (609844) | more than 7 years ago | (#17007846)

The Russians already use it, but mostly for speed. It isn't all that usefull for stealth. (As already mentioned.)

So it's not useful for submarines, but for many surface ships it is very useful. And for torpedos it is killer. IIRC, they have a couple of rocket-powered supersonic torpedos that panicked the US Navy when first demonstrated...

Re:Don't some military ships use this? (3, Informative)

jfp51 (64421) | more than 7 years ago | (#17008058)

Believe you are taking about the Prairie-Masker system http://en.wikipedia.org/wiki/Prairie-Masker [wikipedia.org]

Re:Don't some military ships use this? (0)

Anonymous Coward | more than 7 years ago | (#17008122)

I thought that was still technically classified, jfp...

Don't worry -- I won't report you to the DOD. :-)

Yes and it has been in use for a while (4, Interesting)

LWATCDR (28044) | more than 7 years ago | (#17008120)

http://www.fas.org/man/dod-101/navy/docs/swos/stu2 /NEWIS9_7.html [fas.org]
Some people will confuse the idea of bubbles with cavitation. Cavitation is loud and is avoided but it is caused when a screw manages to cause a phase change. The water turns to vapor and the the bubble collapses making a lot of sound and can even erode the metal on the screw.
The bubble of air that the navy uses don't collapse so no noise instead it acts like an insulator.

I wonder if you could use the exhaust gases of the ship for the bubbles for shipping application? You would have to cool the gas first but it might be a bit if a free lunch.

Already used in military ships as sound proofing (0)

Anonymous Coward | more than 7 years ago | (#17007476)

Hi:

This is done to mask the sound of the ship to lower sonar's ability to hear it. There's a follow-up system for squirting air into the wake to dispell the noise created for similar reasons. However, the primary benefit is to reduce detectability. I'd hate to imagine the fuel consumption needed to drive air compressors at such a rate to reduce friction as the primary goal.

--Not an engineer.

or better yet . . . (0)

Anonymous Coward | more than 7 years ago | (#17007484)

why not just skip the "we reduced friction with bubbles" and proceed directly to the "we ooze along in a cloud of our own mucous" technology?

Re:or better yet . . . (1)

ross.w (87751) | more than 7 years ago | (#17007746)

That would be the polymer idea mentioned in the article. When these are used as flocculants in sewage treatment, the batching and dosing plants need to be equipped with special high grip flooring because otherwise the floor gets lethally slippery if you spill this stuff and get it wet. Think banana peel times ten.

My vote (1)

llamalicious (448215) | more than 7 years ago | (#17007512)

Is to use a nuclear powered fully-submersed shell which uses super-cavitation to acheive high-speeds with minimum drag, and have it generate a powerful magnetic field above it to suspend a freighter above the water. Like a water-based, self-contained maglev.

Sure it's total impossible and you'll whine about minor problems like air friction of the freighter, the power requirements for doing something like this, and stabilizing the boat above the submersed shell, but wouldn't it look cool!

As long as we are dreaming ... (1)

with_him (815684) | more than 7 years ago | (#17007770)

Is to use a nuclear powered fully-submersed shell which uses super-cavitation to acheive high-speeds with minimum drag, and have it generate a powerful magnetic field above it to suspend a freighter above the water. Like a water-based, self-contained maglev.

Sure it's total impossible and you'll whine about minor problems like air friction of the freighter, the power requirements for doing something like this, and stabilizing the boat above the submersed shell, but wouldn't it look cool!
And in the process we use the heat to change the viscosity of the water around the submerged part. Further we use the excess electricity to split the H2O into the components Hydrogen and Oxygen. Then we have giant gas collectors attached to the side of the tanker and we use the gas in the afterburners. Now wouldn't it SUPER cool to see a supertanker levitating in mid air with afterburners going?

And as long as we're dreaming ... (1)

Volante3192 (953645) | more than 7 years ago | (#17007996)

...I'd also like a pony.

Boy Scout Race (2, Funny)

frieza79 (947618) | more than 7 years ago | (#17007528)

With this knowledge, no one will be able to touch my son's boat at the next Boy Scout's boat race!!!

silly bubbles (0)

ealbers (553702) | more than 7 years ago | (#17007534)

Putting bubbles around a ship will decrease its displacement, thus making it sink more to compensate for the loss of displacement, it will sink until it displaces exactly the same weight in water as the ships weight. I doubt this will help with friction, as you must, by definition displace physically the same amount of liquid, only now its harder to do, and the ship must 'sink' deeper in the water to displace it. Seems like smoking fairy bubbles to me

Re:silly bubbles (0)

Anonymous Coward | more than 7 years ago | (#17007980)

Yeah, wow, I'll bet those dumb naval engineers never thought of that! Just goes to show you that No Child Left Behind thing is working.

You're right! (1, Funny)

Anonymous Coward | more than 7 years ago | (#17008186)

And all those engineers are wrong. I just hope they all read /..

The technology already exists! (2, Funny)

GoRK (10018) | more than 7 years ago | (#17007554)

Why bother reinventing the wheel when they could just glue a bunch of air hockey tables to the outside of a boat?

no other technique??? (5, Funny)

DerekTomes (1024783) | more than 7 years ago | (#17007564)

"...There is currently no other technique in naval architecture that can promise such savings..."
Except sails.

Re:no other technique??? (1)

bill_kress (99356) | more than 7 years ago | (#17007782)

Damn, where are my mod points when I need 'em.

Well, I give this a +1 funny and a +1 insightful!

Hmm, then it might be too high, might have to give it a -1 overrated too.

Re:no other technique??? (1, Insightful)

dfenstrate (202098) | more than 7 years ago | (#17007786)

Sails and tight schedules don't go well together.

Re:no other technique??? (5, Informative)

AK Marc (707885) | more than 7 years ago | (#17007932)

They go great together. When you have the wind, you raise the sails and turn the engines down. When you don't have the wind, you take the sails down. You have the same speed either way and are never off schedule. The difference is that you get there using less fuel when you use the sails in addition to the engines.

Re:no other technique??? (1)

the-empty-string (106157) | more than 7 years ago | (#17008038)

Sails and tight schedules don't go well together.
True, but they wouldn't have to be used as a complete replacement of existing engines. Sails could be used as part of a hybrid system, similar to the way electric propulsion complements gasoline engines in hybrid cars. The combination could provide significant savings.

Erm... (0)

Anonymous Coward | more than 7 years ago | (#17008090)

The 19th century called, it wants its ships back.

Seriously, though, when the age of sail was coming to a close, the first engine-powered ships still had sails, for exactly that reason - save fuel when the wind is good, save time when you're stuck in the doldrums.

Re:no other technique??? (1)

DerekTomes (1024783) | more than 7 years ago | (#17008076)

You're right, you cannot rely on sail power if you have a tight schedules. But that doesn't mean you can't take advantage of the savings it gives you. If the wind is blowing the right way, use it and save gas. And they could also try the little dimples on the hulls of the ships (like on golf balls).

Re:no other technique??? (1)

qwijibo (101731) | more than 7 years ago | (#17007790)

Sails don't sell oil you hippy. =)

I'd like to see blimps used for non-time-sensitive over land shipping. I saw an article in popular science many years ago talking about the feasability of blimps for moving things as large as tanks. For non-wartime/non-hostile equipment movement, it seems like that would have to be cheaper than ditching everything and replacing it later.

Re:no other technique??? (1)

jandrese (485) | more than 7 years ago | (#17008190)

Blimps are real gas guzzlers if you're going against the wind though. Even if you're going with the wind I doubt there are any savings at all compared to freight trains, and they're slower than trains to boot. Using blimps for shipping just doesn't seem like a good idea to me, unless you're shipping to some area that doesn't already have infrastructure (out in the middle of nowhere), in which case it would probably be more fuel efficient than the helicopters/light aircraft you would otherwise have to use.

Re:no other technique??? (2, Insightful)

ductonius (705942) | more than 7 years ago | (#17007814)

Except sails.

That wouldn't be saving energy, that would be collecting it from an ubiquitous source. A sailing ship equipped with systems this research develops would outperform one without them.

Somehow using wind to suppliment conventional fuels is a good idea though. Why pay for what you can get for free?
clicky --> http://www.skysails.info/ [skysails.info]

Re:no other technique??? (0)

Anonymous Coward | more than 7 years ago | (#17008064)

How about you use both sails and the bubble stuff and be really cool?

Re:no other technique??? (1)

ductonius (705942) | more than 7 years ago | (#17008134)

Didn't I just say that?

Hire Terry Pratchett (1)

Mahy (111194) | more than 7 years ago | (#17007568)

Since he wrote about this technology in "Jingo" (putting the discovery in the mouth of Leonard of Quirm, way back in 1997), I would guess that this is not a cutting-edge discovery.

Hmmm, much less buoyancy sitting in bubbles... (0)

Anonymous Coward | more than 7 years ago | (#17007628)

The ship will try to displace it's weight in the water. Bubbles have way less buoyancy and the ship will try to sink down thru the layer of bubbles, as the trapped air in the bubbles will not be able to support the weight of the ship and the air will compress greatly.

One of the theories of the Bermuda Triangle is that vast deposits of methane hydrate ice at the bottom of the sea suddenly turns loose and floats up to the surface. Any ship happening to be sitting there when the methane bubbles come up underneath it sinks pretty quickly as the frothy water cannot support the weight. When the methane reaches the surface and there is suddenly plenty of oxygen, there also suddenly comes a major fire / explosion hazard if any ignition source is nearby.

*Tiny* bubbles. (0)

Anonymous Coward | more than 7 years ago | (#17008072)

They're talking about tiny bubbles, more like a film of bubblage than a roiling cauldron. (Or, in the case of the air cavities also mentioned, large voids which would function more or less the same as somewhat leaky sections of hull, just without the actual hull wall being at the water-ship interface.)

Excuse me, but... (0)

Anonymous Coward | more than 7 years ago | (#17007636)

...this is not one of Roland Piquepaille's excellent blog posts. Why should I trust this source?

Don Ho knew it (0)

Anonymous Coward | more than 7 years ago | (#17007666)



Tiny bubbles under my ship
make the hull super slick
tiny bubbles make our trip
fast and silent and super scientific

So here's to the scientists
who help us cross the sea
I can't wait to make that journey

Bzzzt (4, Informative)

Dan East (318230) | more than 7 years ago | (#17007672)

When you consider that 90% of the world's goods are transported by sea

Bzzzt. The submitter misstated the article, so this statement is flat out wrong.

From the article (emphasis mine):
in 2003 more than 90 per cent of all goods that were sent around the globe went by ship

So in the context of global shipping, 90% of goods are transported by sea. Obviously far, far less than 90% of the world's goods are transported globally in the first place.

Dan East

Re:Bzzzt (1)

frank_adrian314159 (469671) | more than 7 years ago | (#17007884)

Obviously far, far less than 90% of the world's goods are transported globally in the first place.

Yeah, but they're working on that, too...

Old news? (1)

Antony-Kyre (807195) | more than 7 years ago | (#17007686)

I could have sworn I heard about this idea years ago. I think it could have been 6 years ago. I remember something about this.

Re:Old news? (2)

Control Group (105494) | more than 7 years ago | (#17008044)

The first I ran across a similar concept (and one mentioned in TFA) was, in fact, on slashdot. It might have been this article [slashdot.org] , though that references earlier stories I couldn't find in a quick googling. Of course, the Scientific American article the /. writeup links to is MIA, so I can't be sure that's the blurb I'm thinking of.

But yeah, if you've been reading /. for long enough, you've seen something like this before.

Re:Old news? (1)

Antony-Kyre (807195) | more than 7 years ago | (#17008158)

Unfortunately, archive.org doesn't even have it due to the robots.txt exclusion.

I sure wish someone would invent a way to surf the Internet in the past.

In case anyone is interested (4, Interesting)

noewun (591275) | more than 7 years ago | (#17007714)

In what

The idea of air cavities has much in common with supercavitation, in which a submerged object such as a torpedo creates a single large bubble around itself. This slashes skin friction, bringing remarkable speeds within reach (New Scientist, 22 July 2000, p 26). Perhaps not surprisingly, Russian engineers who first developed supercavitating torpedoes have not only done plenty of research on air-cavity lubrication for ships, but have also put their ideas to work.

refers to: Shkval [fas.org] . Scared the bejesus out of the U.S. Navy.

Not really the same. (2, Interesting)

Poromenos1 (830658) | more than 7 years ago | (#17008192)

The supercavitational bubble is vacuum, not air. This is also the reason why the torpedo cannot be manoeuvred with traditional means once fired (since there is no water anywhere around it).

This works best at slow speeds (4, Interesting)

nels_tomlinson (106413) | more than 7 years ago | (#17007720)

I haven't yet read the fine article. I do know just a bit about naval architecture. This should help with skin friction, which is the big deal at low speeds. For higher speeds, the resistance which comes from making the wake is the big deal, since the wave-making resistance increases roughly as the square of the speed.

So, what's ``low speed?'' That's probably going to be any speed much below sqrt(waterline length in feet), with units of knots. So, for a 400-foot long ship, anything less than 20 knots is in the speed range where this is likely to matter. For a 900 footer, anything less than 30 knots. Most ships travel in that low speed range, so this could be practical.

My input (1)

iamdrscience (541136) | more than 7 years ago | (#17007738)

Kodama is director of the Advanced Maritime Transport Technology Department at Japan's National Maritime Research Institute (NMRI) in Tokyo. His work is just one of several major programmes under way in the US, Russia, Japan and Europe that focus on how to make ships more slippery.
Based on my experience in the bathtub, an easy way to make a more slippery craft is to cover it with soap. I think this would scale up nicely, but I'm not sure how they would make a freighter in the shape of a rubber duck.

Re:My input (1)

Bluesman (104513) | more than 7 years ago | (#17007850)

Funny you should say that.

Have you ever tried to use soap in salt water? It just doesn't work. It's not slippery, it's more like trying to wash with a pumice stone.

I had the opportunity to try this while sailing to Bermuda when the wind died completely. Hoped to get a nice bath after three days of no showering, but it didn't work.

Re:My input (1)

advocate_one (662832) | more than 7 years ago | (#17008238)

I had the opportunity to try this while sailing to Bermuda when the wind died completely. Hoped to get a nice bath after three days of no showering, but it didn't work.
you used the wrong soap... there are soaps designed for use with sea water... just google for it... yeah, I know you were caught out, but next time... take some along and you can then save your precious fresh water for drinking.

Talk to Speedo (1)

T-Ranger (10520) | more than 7 years ago | (#17007788)

Olympic swimmers are all wearing high tech swimsuits. Now, I don't exactly recall the spoken content of the bit piece that I saw, but there is some kind of magicness in that fabric that I think does just what this is talking about, passively. Acres of spandex?! Let the dont-mind-long-voyages-away-from-women jokes begin!

From now on, we will travel in tubes! (1)

XxtraLarGe (551297) | more than 7 years ago | (#17007904)

Phah! Bubbles? That's lame. Tenacious D seemed to have an even better idea when they toppled City Hall [azlyrics.com]

The second decree: no more pollution, no more car exhaust, or ocean dumpage. From now on, we will travel in tubes! Get the scientists working on the tube technology, immediately!

slow news day ? (1)

cyberianpan (975767) | more than 7 years ago | (#17007948)

This is a February 2006 article.... slow news day ? Also the artcile is highly speculative , eventhe 20% isn't certain...

Barking up the wrong tree (4, Funny)

Control Group (105494) | more than 7 years ago | (#17007956)

What they ought to do is replace the oceans with frictionless liquid helium. That would be way more effective.

Everyone is wondering... (1)

binaryloc (1028364) | more than 7 years ago | (#17007958)

Will the computers that control the pumps that shoot the air run on linux?

Isn't that called a hovercraft? (1)

dlleigh (313922) | more than 7 years ago | (#17007960)

Or does one big bubble not count?

"far less" is relative? (1)

null etc. (524767) | more than 7 years ago | (#17007994)

and using far less fuel, than ever before...


20% increase in efficiency will result in the consumption of "far less" fuel? Far out!

another sweet idea (1)

ILuvRamen (1026668) | more than 7 years ago | (#17008004)

I'm no engineer but if they hook really, really big hot air balloons up to the exhaust towers, wouldn't that lift it noticeablly too? A couple more ideas like that and they'll just be big airplanes lol.

How will we see Godzilla (1)

gelfling (6534) | more than 7 years ago | (#17008012)

when he bubbles up out of the ocean then?

sea mines use bubbles to crak ships (1)

adaminnj (712407) | more than 7 years ago | (#17008106)

there are some sea mines that create a bubble to lessen the support that carrys the ship and cracks the hull.

I'm not a mechanical engineer nor have I looked at the math on this tech. but if you ask me I think it might not have to much of a chance based on the bubbles size and number of them it would take to support a tanker standing still let alone at speed.

as well there is a theroie that the bermuda triangle takes down ships with the release of carbon bubbles from the sea floor

it will be intresting to see it work.

bubbles from the back (1)

planckscale (579258) | more than 7 years ago | (#17008142)

Seems to me the most bubbles I see when I'm on a big boat are off the stern, created by the engines and hull displacement themselves. If there was a way to channel those bubbles to the bow of the ship, you may not need extra engines/bubble makers on the front. Perhaps something like an in-hull channel that forces the bubbly soup from the stern up and under the ship, and ejects in under the bow. Either that or find a way to make the ships "Front-wheel drive" so to speak, and have the engines under the bow of the ship. This way the engine's propellers are creating the bubbles, and naturally give lift. Or if it's just the displacement that creates most of the bubbles off the stern, have the ship push a suspended or rigid bubble-making displacer off the bow of the ship. As the ship starts to move, the displacer could be lowered into the sea. Bubble boom could also contain air jets that force streams of bubbles under the bow.

Bathtub bubbles (4, Funny)

kitzilla (266382) | more than 7 years ago | (#17008184)

"Junior! What are those bubbles in the bathtub?"

"Just reducing drag, Ma."

I can see & hear it now...Blow!...tiny bubbles (0)

Anonymous Coward | more than 7 years ago | (#17008244)

Back in the day there used to be ships traversing the high seas with slaves pulling at oars and a slave master pounding a big drum. I can see it now - a large ship with the crew hanging over the edge blowing bubbles with very long straws listening to the drone of Don Ho's "Tiny Bubbles"....

This was tried with submarines in the 60's (1)

davidsheckler (45018) | more than 7 years ago | (#17008262)

For different purposes, they we're trying to obscure active sonar, of course it created more noise than it absorbed so it wasn't really feasible. It also had the side effect of letting the submarine 'slide' faster through the water. I don't have a reference to back this up, just a conversation I had with an instructor in Sub school in Groton Connecticut.

What about sails? (1)

Yez70 (924200) | more than 7 years ago | (#17008266)

"There is currently no other technique in naval architecture that can promise such savings."

I hate innacurate reporting. Adding Giant Kite-like sails to cargo ships is an alternative as well.

http://www.msnbc.msn.com/id/13325827/site/newsweek / [msn.com]

This is in use now and increases both speed and fuel efficiency far more than the 20% savings the air bubbles promise.

Imagine using both technologies together, or even adding solar panels to the sails for even more efficiency.

http://www.ens-newswire.com/ens/apr2005/2005-04-06 -03.asp [ens-newswire.com]
Load More Comments
Slashdot Login

Need an Account?

Forgot your password?

Submission Text Formatting Tips

We support a small subset of HTML, namely these tags:

  • b
  • i
  • p
  • br
  • a
  • ol
  • ul
  • li
  • dl
  • dt
  • dd
  • em
  • strong
  • tt
  • blockquote
  • div
  • quote
  • ecode

"ecode" can be used for code snippets, for example:

<ecode>    while(1) { do_something(); } </ecode>