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DARPA’s silent MHD magnetic drives for replacing naval propellers

naval-technology.com

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Re: DARPA’s silent MHD magnetic drives for replacing naval propellers

#11

Post by gpm »

If they meet their 90% efficiency target, that's exceeding the efficiency of a normal boat. Just the propeller losses are higher than that (at ~80% efficient [1]).

If it's just some REBCO super-conducting magnets and conductive surfaces it might be reasonably inexpensive too. And without moving parts it could be a maintenance win as well.

I'm no sailor, but at first glance this seems like it would potentially replace all propulsion on boats/ships big enough to justify cooling REBCO. Obviously conditioned on actually reaching that fairly outrageous target.

[1] https://www.britannica.com/technology/naval-architecture/Act...

Re: DARPA’s silent MHD magnetic drives for replacing naval propellers

#14

Post by ChrisMarshallNY »

eqmvii wrote: post #7
rektide wrote: post #3

> If power and efficiency issues are resolved, My gut feel is that this is a pretty grossly inefficient system by nature. Inducing current in seawater just to give magnetic traction something to push off against seems semi absurd.

semi absurd is kinda why DARPA exists!

The Register used to make fun of DARPA, saying things like “where every laugh is a mad cackle.”

Re: DARPA’s silent MHD magnetic drives for replacing naval propellers

#15

Post by atonse »

zrail wrote: post #6

Isn't this the plot for Hunt for Red October?

Yes! I was thinking that as I read it. Alec Baldwin even says magneto hydrodynamic drive.

Yet another example of Tom Clancy’s incredible knowledge of the intricacies of what the military had on their radar and working that into great stories.

Re: DARPA’s silent MHD magnetic drives for replacing naval propellers

#17

Post by acdha »

WhereIsTheTruth wrote: post #2

[flagged]

Do you have a more credible citation? That guy on YouTube seems to be the most common source for this claim and he gets paid for clicks. More mainstream sources don’t seem to think Russia has any particular edge here.

Re: DARPA’s silent MHD magnetic drives for replacing naval propellers

#19

Post by beambot »

eqmvii wrote: post #7
rektide wrote: post #3

> If power and efficiency issues are resolved, My gut feel is that this is a pretty grossly inefficient system by nature. Inducing current in seawater just to give magnetic traction something to push off against seems semi absurd.

semi absurd is kinda why DARPA exists!

While we all communicate using TCP/IP, invented as a DARPA program for robust communication in the event of nuclear conflict...
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