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Cloaking Technology Could Protect Offshore Rigs From Destructive Waves
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."
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
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.
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....
Faster! Faster! Faster would be better!
The last one I saw was this: http://www.newscientist.com/article/dn14829
and: http://discovermagazine.com/2012/jul-aug/06-how-to-make-anything-disappear
Does this invisibility cloak make me look fat?
I was promised a flying car. Where is my flying car?
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.
"Windows is like the faint smell of piss in a subway: it's there, and there's nothing you can do about it." - Charlie Br
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.
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.
systemd is Roko's Basilisk.
Those ocean researchers should really check whether Sandy Island is not actually covered in an invisibility cloak.
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.
<blink>down the rabbit hole</blink>
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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