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Cloaking Technology Could Protect Offshore Rigs From Destructive Waves

samzenpus posted about a year and a half ago | from the almost-perfect-wave dept.

Technology 56

cylonlover writes "Recent years have seen much progress in the development of invisibility cloaks which bend light around an object so it can't be seen, but can the same principles be applied to ocean waves that are strong enough to smash steel and concrete? That's the aim of Reza Alam's underwater 'invisibility cloak.' The assistant professor of mechanical engineering at the University of California, Berkeley, recently outlined how to use variations of density in ocean water to cloak floating objects from dangerous surface waves."

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56 comments

Might look good in a wave tank (0)

Anonymous Coward | about a year and a half ago | (#42070907)

However ocean waves are generally much more random and disorganized than the ones you produce in a laboratory.

Re:Might look good in a wave tank (0)

Anonymous Coward | about a year and a half ago | (#42071025)

I'm sorry, but you are completely full of shit and clearly know nothing about oceanography.

Re:Might look good in a wave tank (1)

Nostromo21 (1947840) | about a year and a half ago | (#42071073)

Aha. Care to share your credentials in fluid dynamics with the rest of the class Mr AC...?

Re:Might look good in a wave tank (4, Informative)

Runaway1956 (1322357) | about a year and a half ago | (#42071779)

No credentials other than 5 years of sea duty with the US Navy. A few months of that time were spent on "rough seas". At least a month of that were on seas that came close to those described in "The Perfect Storm" - often exceeding 60 feet, and at times exceeding 80 feet. No hundred foot seas for me, 80 was enough.

Now - are you ready for it?

Neither the waves nor the swells are very random. I don't believe that anyone can predict them with very much accuracy, as of now, but they are generally predictable. Chop is another matter, entirely. If there is any way to predict chop, I can't imagine what it is. But, chop has very little energy, and has almost zero effect on the stability of a ship, or any other large platform.

I highly doubt the effectiveness of this cloaking device, but if it is somehow capable of mitigating some of the water's force, then we can and will develop the software to better predict the actions of swells and waves.

That said - I don't believe any software will be able to take rogues into account. They are named rogues, because they run counter to prevailing seas, seemingly at random.

Re:Might look good in a wave tank (1)

mcneely.mike (927221) | about a year and a half ago | (#42073165)

Now, see, if the ship you had been on had been using ship camouflage, you'd have been much better off! :)
http://en.wikipedia.org/wiki/Ship_camouflage [wikipedia.org]

Please. (0)

Anonymous Coward | about a year ago | (#42082067)

Please.

Look up Draupner wave in Wikipedia. Look at the graph and stop your flapping showoff mouth about "counter to prevailing seas, seemingly at random".

Re:Might look good in a wave tank (3, Funny)

Anonymous Coward | about a year and a half ago | (#42071087)

I, however, do know about oceanography. And I know that calling the technology a "cloak" is a joke, it's simply interference. I haven't even taken Physics III and I understand the principles behind the technology. A typical rig has water velocity sensors looking horizontally outward close to the surface and downward on the drillin' axis. Such a "cloak" would be pointless because the rig is pragmatically a fixed structure and bad conditions above are the same as bad conditions below. In short, if shit too wild, either up top or down below, you ain't drillin'. If existing patterns of surface waves were that dangerous to rigs, nobody would be rigging.

Prove me wrong.

-- Ethanol-fueled

Re:Might look good in a wave tank (1)

Nostromo21 (1947840) | about a year and a half ago | (#42071115)

Fair nuff. But are there wave-based 'storms' well below the surface anyway? Apart from regular ocean currents, I thought I read that once you get a few metres down it's all status quo. Certainly as far as temperatures are concerned, which don't vary by more than 3 degrees or so once you get 3 or more metres under the surface, same depth vs depth, all the way from the equator to the poles. But what I read may have been full of shit.

Re:Might look good in a wave tank (0)

Anonymous Coward | about a year and a half ago | (#42071139)

Prove me wrong.

Why should we listen to a mere AC?

-- CmdrTaco

Re:Might look good in a wave tank (0)

Anonymous Coward | about a year and a half ago | (#42071201)

I read that once you get a few metres down it's all status quo.

Like a hundred [wikipedia.org] or so. For most practical purposes, surface and deep-water applications are two different beasts. Thermoclines are in fact one of the ways submarines can (and do) avoid detection. Shit, if the DoD's obsession with the cold war actually had merit, there might even be a real use for this technology.

Re:Might look good in a wave tank (2)

ColdWetDog (752185) | about a year and a half ago | (#42071331)

It appears that the 'cloaking device' would create impulses in the water that would null out at least part of the big nasty surface wave. To do this, it has to be coupled to the surface - otherwise no energy would get imparted.

The physics of wave amplification and cancellation are well established. I imagine that we have the technology to look at the waves coming at the rig, figure out the waveforms and come up with 'counter' waveforms. I'm having problems, however, figuring out where he is going to get the energy to make the counter waves.

And for once, I have to agree with EF, it doesn't appear to be work like other cloaking' devices (where the waves are bent around the object), it just seems to be waveform cancellation. Of course the TFA has little in the way of useful info....

Re:Might look good in a wave tank (-1)

Anonymous Coward | about a year and a half ago | (#42071449)

Faggoty fluid dynamics motherfuckers thinking that their first-year finite-voulume CFD simulations justify the $40,000 waste of money. Here's a hint, idiots, most math is done with trig. Especially underwater math.

Nothing is more faggotty and useless than retard idiots.

Re:Might look good in a wave tank (0)

Anonymous Coward | about a year and a half ago | (#42071469)

No, it is still like other cloaking technologies, in the sense it bends waves around the rig. In this case, instead of bending them laterally around the rig, it bends them downward where they convert into a different type of wave that travels within a particular layer below the surface. This has advantages that the wave is structured differently when going through the below surface layers, and can potentially do much less damage to a structure (alternatively, takes much less structure to protect against potential wave damage).

And normally surface waves driven by wind diminish to less than a few percent of their surface strength about half a wavelength down (about 50 m), so conditions below are not normally the same as above. In other words, the AC post signed "Ethanol-fueled" is wrong on just about every account.

Re:Might look good in a wave tank (1)

ls671 (1122017) | about a year and a half ago | (#42071527)

I'm having problems, however, figuring out where he is going to get the energy to make the counter waves.

Energy, oil companies? Not a problem. Do you know how much energy it takes to pull a several miles drill string out of the ground when comes the time to change the drill bit? Hint: the hook that grabs the string is 15 to 25 tons on triple rigs (they stack 3 pipes on the derrick when pulling out, to make things go faster).

Now, do you know how much energy it takes to drive and the size of the pumps that push drilll fluid inside the drill string ?

In order of magnitude, cost efficiently speaking, I think it would be feasible.
 

Re:Might look good in a wave tank (1)

ls671 (1122017) | about a year and a half ago | (#42071553)

Furthermore, once the hole(s) in production, just use the natural gas coming out to power the "cloaking" device instead of burning it. That's the big flame you see on production platforms. They just waste it because it is to risky and not efficient (money wise) to store.

Hell, on production platforms where not much natural gas comes out, just use crude oil. Some super tanker boats run on crude oil so energy sources do not seem like a show stopper anyway.

Re:Might look good in a wave tank (0)

Anonymous Coward | about a year and a half ago | (#42071651)

Deep water ocean waves in a storm can easily contain more than 2 MW of power per meter of exposed side to the wave. With 50 m wide for a larger platform, that is 100 MW of power. If you have some sort of wave mitigating structure around the platform, it could be even larger. As is though, 100 MW would be on par with a dozen large tug boats, possibly more than what was used to position the larger platforms, and definitely more than they normally have on hand. It would seem measures to minimized what is exposed to the waves and to redirect waves instead of trying to cancel them out would be far more efficient, even for oil companies and their far from limitless budget, energy or otherwise.

Re:Might look good in a wave tank (1)

ls671 (1122017) | about a year and a half ago | (#42071753)

Re:Might look good in a wave tank (0)

Anonymous Coward | about a year and a half ago | (#42074595)

The largest one listed in that document is 20 MW, do drilling platforms frequently have half a dozen of those already? If they had that much power available, why are they not self propelled instead of using about the same power in towing boats when moving them around? Maybe it is not cheap to have that much power available and configured to use for things like moving water around the platform... assuming waves can be generated with any efficiency.

Re:Might look good in a wave tank (1)

ls671 (1122017) | about a year and a half ago | (#42074931)

The diesel electric rig I used to work on had indeed 10 of them and it was a plain on land rig. That rig wasn't the biggest either. Bigger = able to go deeper.

Also, as another poster as noted, if you read TFA, that kind of power might not be needed at all. The "cloaking" device would be installed at the bottom of the ocean and it is not clear how much power it would require if any...

Re:Might look good in a wave tank (1)

ColdWetDog (752185) | about a year and a half ago | (#42075187)

I know the pics show the device on the bottom but seemingly that would work only for shallow water rigs and not for the deeper platforms. Still would need large amounts of power (I guess). And dealing with a 100 MW power plant (or the output of same) on the bottom of the ocean is a pretty big engineering challenge.

Nice to have some real numbers and a better diagram.....

Re:Might look good in a wave tank (1)

lgw (121541) | about a year and a half ago | (#42076759)

I don't see why people are assuming this would need a ton of power. How much power does a mirror consume, or a quarter-wave-plate? Changing the impedance of the water locally, or otherwise changin its dynamics, so that the wave energy takes a less destructive form as it passes the rig doesn't require power on the scale of the waves.

Re:Might look good in a wave tank (0)

wonkey_monkey (2592601) | about a year and a half ago | (#42071761)

Do you know how much energy it takes to pull a several miles drill string out of the ground when comes the time to change the drill bit?

No, do you?

Now, do you know how much energy it takes to drive and the size of the pumps that push drilll fluid inside the drill string ?

No, do you?

In order of magnitude, cost efficiently speaking, I think it would be feasible.

Based on what numbers, or is this just a hunch?

All of this may be moot anyway, since I don't see anything in the article about energy having to be expended, except in the initial construction of seabed shapes.

He found that by placing a corrugated or wavy pattern tuned to particular wavelength on the seabed it would cause surface waves to temporarily become internal waves.

Re:Might look good in a wave tank (1)

ls671 (1122017) | about a year and a half ago | (#42071803)

Good point, I never said that kind of energy was required. I just wrote that it was available to oil platforms ;-)

http://slashdot.org/comments.pl?sid=3268803&cid=42071753 [slashdot.org]

Re:Might look good in a wave tank (0)

Anonymous Coward | about a year and a half ago | (#42071853)

it doesn't appear to be work like other cloaking' devices (where the waves are bent around the object), it just seems to be waveform cancellation.

There is no cancellation according to TFA that I read, only transference. It seems like they are using a waveguide pattern to transfer surface waves to a below-surface cline.

Re:Might look good in a wave tank (1)

hackertourist (2202674) | about a year and a half ago | (#42072665)

TFA states that no, they won't be creating impulses in the water. Instead, they noticed that
a. waves can travel on the surface, or at the thermocline.
b. waves interact with and can be influenced by the seafloor.
They propose to shape the seafloor so that the waves move from the surface to the thermocline. This means the wave is no longer visible at the sea surface.

Re:Might look good in a wave tank (1)

Runaway1956 (1322357) | about a year and a half ago | (#42071797)

Sea conditions are felt more than a "few meters down". Anecdotal evidence suggests that a storm's actions can be felt at 500 feet, and really severe storms even further. I've never been underway in a sub, so I have no firsthand knowledge. Bubble heads will tell you that they dive when the seas are rough. The rougher the seas, the deeper they want to dive.

I don't think any storms are likely to be felt past 500 meters, or yards.

Re:Might look good in a wave tank (0)

Anonymous Coward | about a year and a half ago | (#42071591)

Um. Floating platforms are still quite common. As a simple example, the Ocean Ranger disaster off the coast of Newfoundland. The rig failed because of conditions at the surface. There were major rig design flaws, but deflecting the worst of the storm away from the surface would still have potentially saved lives.

Re:Sound Studios (1)

hoboroadie (1726896) | about a year and a half ago | (#42074391)

Music tends to produce a pretty random array of waves, yet I've seen active acoustic stuff (bass traps) in studios that fixed all the deleterious waves that would ruin the recording. Same principles at work, methinks.
Maths FTW!

Will need... (1)

c0lo (1497653) | about a year and a half ago | (#42070923)

Will need lotsa beer to significantly change the seawater density around the platform.
Just sayin'

The utility of math is fascinating... (5, Informative)

fuzzyfuzzyfungus (1223518) | about a year and a half ago | (#42071131)

I am perpetually impressed by how useful mathematics derived from a few abstract axioms can actually be in modelling the real world. Further, it is always fascinating to see the strange overlaps where a single mathematical abstraction proves useful in the examination of two seemingly unrelated phenomena...

It is apparently so; but the idea that waves made of seawater and 'waves' that function as models of certain aspects of the behavior of electromagnetic radiation is always deeply surprising.

Re:The utility of math is fascinating... (0)

Anonymous Coward | about a year and a half ago | (#42072421)

That mentioned, I'm still wondering whether anything like "reactive current component" could exist in water lines, only so that it would always be generally negligible.

Re:The utility of math is fascinating... (0)

Anonymous Coward | about a year and a half ago | (#42074935)

I consistently fail to understand why people feel like the similarity between waves of different energy types should propagate differently and, thus, require different math to explain. Waves made of seawater are simply waves of kinetic energy. Electromagnetic radiation are simply electromagnetic waves. The basic principles of wave mechanics don't change simply because you change the medium. I find your bemusement equally bemusing.

Must be something in the water (1)

sparkeyjames (264526) | about a year and a half ago | (#42071133)

Someone getting an early jump on April 1st?

Is it Romulan? (1)

Anonymous Coward | about a year and a half ago | (#42071309)

Did they get this cloaking technology from the Romulans?

Re:Is it Romulan? (1)

Daniel Klugh (1935646) | about a year and a half ago | (#42071459)

How does being invisible protect you from ocean waves? Perhaps they confused "invisibility" with "intangibility". Then again, the Cloaking Device on Star Trek worked via the Deflector Screen (Stargate: Atlantis coppied this) so it's understandable if stupid people get confused.

Re:Is it Romulan? (0)

Anonymous Coward | about a year and a half ago | (#42071961)

Both solutions employ alterations in medium density to redirect wave patterns. I was expecting TFA to describe a solution like hydrolysing some area around the platform to transfer wave energy around it.

Instead, the most relevant medium density appears to be the difference in density between the bedrock and the water: the solution described uses reflection patterns to transfer wave energy from the surface to a deeper channel. That deeper channel also exists because of a density boundary -- but that density boundary serves as a waveguide, not a deflective shield.

Does this invisibility cloak? (2)

dutchwhizzman (817898) | about a year and a half ago | (#42071579)

Does this invisibility cloak make me look fat?

Ha! You can't see me! (1)

dacarr (562277) | about a year and a half ago | (#42071805)

I suppose this would assume that waves have some intelligence, and are attacking these ships. I'm of the opinion that these waves are more like the Ravenous Bugblatter Beast of Traal, where you would be better off covering your eyes with a towel to fool them into thinking the ship - or at least, the crew - are invisible.

Well, it would probably just do as much good.

Interesting idea, but how would you put it to use? (1)

LostMonk (1839248) | about a year and a half ago | (#42071929)

As I understand, to generate that cloak you need to create/modify underwater layers by changing salinity or temperature or direction. It all comes down to manipulating HUGE masses of water -- meaning investing HUGE amounts or energy. It's a cool idea but the implementation is in the regions of sci-fi.

Re:Interesting idea, but how would you put it to u (2)

wonkey_monkey (2592601) | about a year and a half ago | (#42072887)

As I understand, to generate that cloak you need to create/modify underwater layers by changing salinity or temperature or direction.

You misunderstand:

He found that by placing a corrugated or wavy pattern tuned to particular wavelength on the seabed it would cause surface waves to temporarily become internal waves.

The two layers of water are a natural phenomenon which allow the waves to be transferred underwater.

Re:Interesting idea (1)

LostMonk (1839248) | about a year and a half ago | (#42073409)

He found that by placing a corrugated or wavy pattern tuned to particular wavelength on the seabed it would cause surface waves to temporarily become internal waves.

The two layers of water are a natural phenomenon which allow the waves to be transferred underwater.

"Tuned to particular wavelength..." how is that a natural phenomenon?

Re:Interesting idea, but how would you put it to u (1)

drinkypoo (153816) | about a year and a half ago | (#42073121)

I have not RTFA because that's how it is but there's another fine way to change the density of water, you inject air. They can store air pressure in a weighted cylinder, water columns... etc etc

other way around (5, Funny)

ssam (2723487) | about a year and a half ago | (#42072009)

Oil rigs are pretty good at exploding on their own without huge waves. we need something to cloak the ocean (and the atmosphere) from from the effects of oil rigs. soviet russia you're our only hope.

Spars (0)

Anonymous Coward | about a year and a half ago | (#42072349)

Do we really need this? Nowadays the spar platform are used a lot in the open sea. Their all around round hull should divert wave hits efficiently, while massive counterweight below keeps the structure stable enough to not snap the pumping tube.

Explains the missing island? (2)

wvmarle (1070040) | about a year and a half ago | (#42072959)

Those ocean researchers should really check whether Sandy Island [slashdot.org] is not actually covered in an invisibility cloak.

"Cloaking" (1)

nurb432 (527695) | about a year and a half ago | (#42073231)

The soon to be over used buzz word of 2013..

shield, not cloak (1)

tverbeek (457094) | about a year and a half ago | (#42073359)

While the technology might have the same basis as these cloaking efforts, this should more properly be described as "shields".

Re:shield, not cloak (1)

Greg Hullender (621024) | about a year and a half ago | (#42076009)

Yeah, everyone likes "invisibility cloak," but I don't see it.

--Greg :-)

wait... if the waves cannot see the oil rig (1)

1800maxim (702377) | about a year and a half ago | (#42073473)

then they won't smash against it? They'll just pass right through, because the rig is, umm, invisible?

They should apply it to cloaking cars. Then there'll be no accidents. Very practical.

Re:wait... if the waves cannot see the oil rig (1)

cellocgw (617879) | about a year and a half ago | (#42075727)

Good grief. Is everyone suffering from toomuchturkey stupidity today?
You muck with the waves coming in so as to force local interference effects. If you did it right, there's a node at the platform and bigger waves somewhere else that don't affect the platform.

Sheesh.

in other news: "bring the oil barrels!" 150 y ago? (1)

Herve5 (879674) | about a year and a half ago | (#42073615)

Long, long ago when I was young, I used to read adventure tales.
All those that happened at sea had the mandatory storm scene of course -- and each time, classically, the pirate captain (or whatever novel hero) suddenly decided to drop oil on the terrible sea, which by this way turned way cooler.

Mind you, I even tried this myself!

Now, of course, you need, and will waste, oil. I understand it's not fashion nowadays...

Re:in other news: "bring the oil barrels!" 150 y a (1)

lgw (121541) | about a year and a half ago | (#42076803)

There was a SciAm article about this mentioned on /. in the last decade or so, finding some merit in altering water composition locally to create locally calmer seas.

This approach alters local impedence through the shape of the ocean floor, not the composition of the water, but it's the same basic idea.

Ogg say Need Gauusian diffusion resonance window (2)

TheRealHocusLocus (2319802) | about a year and a half ago | (#42074239)

Not single pure damping frequency of circular ripples on ocean floor as depicted in simple diagram. Ogg say using single frequency like silly noise cancellation experiment where complex wave beat at edges of cancelling cone to make frog whisper artifact or low frequency beat that make heavy furniture walk around room and make dust bunny dance.

Ogg say use simulation to find most potentially harmful frequencies to oil platform and plot bell curve around them and make concentric patterns of bumps on sea floor not simple ripple, the bumps' separation along radius correspond to harmonics of range of harm frequency. Ogg say put shallower bumps with wider separation around outer edge of sea floor and dense but high bumps immediate surround oil rig and under it.

Because Ogg say only fool want to cancel single favorite wave frequency because nature love to laugh at fool who do so, nature just whistles off key and the fool's brick house go down and fall on piggies inside. Nature love to generate wave with fundamental logarithmic base off by tiny fraction to drown Egyptian surveyors whose brains full of cubits loving of whole numbers.

But Ogg ashamed because in place of egghead math smart magic that will not work Ogg use maths to introduce Gaussian harmonic and what is more Gaussian than a bunch of rocks so Ogg back to rocks again, yes pile a bunch of irregularly shaped rocks on ocean floor just like do on surface by peoples who have no need for maths because they just know to pile up rocks to resist the ocean. Rocks different shape they know Gaussian distribution better than Ogg.

Rocks really smart. Ogg say, rocks rock.
 

Slashdot Luddites (2)

Required Snark (1702878) | about a year and a half ago | (#42076691)

This is an interesting concept, which might have a practical application. By reading the article I learned something and I found it interesting. This is, by definition, "News for Nerds".

As typically happens here on Slashdot, most of the comments deliberately ignore the technical content and make bad irrelevant jokes and/or trash the researcher for being stupid. The person who wrote the original paper is clearly a very intelligent and accomplished academic and doesn't rate this kind of mindless attack. You don't get on the faculty at UC Berkeley by being less then competent.

The "cloaking" description was clearly written by the semi-literate incompetent hack who wrote the fluff piece that quoted the original research. They were trying to tie this research into the recent publicity on electromagnetic cloaking with microwaves and did a very bad job. Any criticism or analysis based on the idea of cloaking is obviously bogus and irrelevant.

From what I could glean from the garbled information, this technique is applicable for the conditions found in deep water oil drilling platforms. It seems that it could decrease the energy of large waves by channeling some of their energy into the water density boundary layer below the rig, providing an extra margin of protection. I doubt that it would diminish waves at all frequencies, but it would be tuned for the most destructive energy band. If it is practical it would be very useful.

Ogg is dumber then a box of rocks. If dumping a bunch of random sized rocks on the ocean floor would protect an oil rig then they would already be doing it. These things are so expensive that if this worked it would be cheap insurance and standard to the industry. To the best of my knowledge dumping rocks is done in shallow water to protect coastlines and harbors, not in deep water. Even if Ogg knows how to spell "Gaussian harmonic" that doesn't mean he is refuting the content of the academic paper. The dumb description just says "ripples", which could actually be a structure like Ogg described. Ogg is throwing stones at a straw man. Ogg's critique is at the same level as a chimpanzee throwing it's shit at something, and has a similar intellectual content.

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