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Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while simultaneously helping it avoid detection.
The idea originated at Duke University in 2011 when researchers outlined the general concept. By matching the acceleration of the surrounding water to an object's movement, it would theoretically be possible to greatly increase its propulsion efficiency while leaving the surrounding sea undisturbed. The theory was an extension of the group's pioneering work in metamaterials, where a material's structure, rather than its chemistry, creates desired properties.
Six years later, Yaroslav Urzhumov, adjunct assistant professor of electrical and computer engineering at Duke, has updated the theory by detailing a potential approach. But rather than using a complex system of very small pumps as originally speculated, Urzhumov is turning to electromagnetic fields and the dense concentration of charged particles found in saltwater.
Dean Culver, Yaroslav Urzhumov. Forced underwater laminar flows with active magnetohydrodynamic metamaterials. Physical Review E, 2017; 96 (6) DOI: 10.1103/PhysRevE.96.063107
(Score: 3, Interesting) by c0lo on Thursday December 14 2017, @09:09AM (12 children)
From TFA
Enormous energy requirements, eh?
At over 1.2-or-so volts, water electrolyzed. Assuming one doesn't eliminate the same by electrolysing everything around, the 'enormous energy requirements' should come from ginormous currents.
Yeah, right, now tell me about those ohmic losses, will you? Are they enough to heat that water around the 'tincan' you want stealthy to 'pasteurize' the content?
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by c0lo on Thursday December 14 2017, @09:12AM (2 children)
Fucking autocorrect!!!
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by MostCynical on Thursday December 14 2017, @09:20AM (1 child)
Does it count if you only use your thumbs?
"I guess once you start doubting, there's no end to it." -Batou, Ghost in the Shell: Stand Alone Complex
(Score: 2) by c0lo on Thursday December 14 2017, @10:15AM
Fat fingers. I'm using a stylus - equiv 1-finger typing.
Fortunately, 2 hours/day only, while travelling.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 3, Informative) by Anonymous Coward on Thursday December 14 2017, @10:28AM (3 children)
Cloaking the electromagnetic emissions themselves seems like a bigger problem.
(Score: 0) by Anonymous Coward on Thursday December 14 2017, @01:19PM (1 child)
I don't think EMR goes far underwater.
(Score: 2) by c0lo on Thursday December 14 2017, @10:35PM
I don't think it will be much E component, they'll probably use DC to drive the water around, AC will only slosh the water.
So rather a largish static magnetic field.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 0) by Anonymous Coward on Thursday December 14 2017, @03:00PM
the water will do that for you free of charge.
(Score: 2) by The Mighty Buzzard on Thursday December 14 2017, @11:31AM (2 children)
So, not really helpful for my john boat then. And here I was all ready to get a bigger trolling motor.
My rights don't end where your fear begins.
(Score: 3, Interesting) by JoeMerchant on Thursday December 14 2017, @12:55PM
Your john boat would benefit more from passive nanomaterial coatings, a good hydrophobic should help getting on-plane faster, once on-plane all this hydrodynamics stuff is much less important. Of course, instead of mucking around with hydrophobic coatings, an extra 10hp in the motor will get you even better speed, if not efficiency - but john boats aren't much about efficiency anyway.
🌻🌻 [google.com]
(Score: 1, Funny) by Anonymous Coward on Thursday December 14 2017, @11:14PM
Save your money. Just go to the oar house and get bigger oars.
(Score: 4, Interesting) by JoeMerchant on Thursday December 14 2017, @12:53PM
Water is a great heat sink, especially when you are moving through it at speed. Get up to 5 knots before engaging the drive - just don't think that you won't be visible to every IR satellite looking at your piece of ocean.
🌻🌻 [google.com]
(Score: 2) by Immerman on Thursday December 14 2017, @02:55PM
Or, the enormous energies go largely to generating magnetic fields within the vehicle, so that relatively low currents in the water will generate the same thrust.