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Why did I think of that?
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Owning a fleet of nuclear submarines puts you in an
exclusive club, owning a fleet of nuclear submarines full of
unstoppable apocalypse rockets is yet more exclusive.
There are several reasons why this is the case, firstly the
existing members agree that no one else should build
extinction ships and you have to listen to them
because of the same ships. The second reason is the
To build a nuclear submarine, you need a nuclear industry.
These are large organizations concerned mostly with
certification, regulation, audits and assorted paperwork
that occasionally build cooling systems around some
physics. To have a nuclear industry, you need a network of
other industries that deliver materials, services and
personnel that do what they're supposed to.
Once you have the prerequisites, you can set about
building a steel tube with a miniaturized nuclear power
station and many explosives. This is tricky. To make it
more difficult, the submarine should be fast, have lots of
endurance, quiet and not blow up if accidentally driven
into a sandbank. More difficult still, it needs to be reliable.
It needs to keep working in harsh conditions since the
shipyards that repair nuclear submarines are right at the
top of the target lists for nuclear submarines.
Much of the complexity and cost derives from the nuclear
fission reactors used as a power source. Typically, a 50-500
MW reactor is used to make steam to drive a turbine for
propulsion and electrical power to run everything else.
Should the reactor go wrong, you can end up with a
meltdown that sends you right to the bottom of the
So lets simplfy the whole arrangment. Do we need the
steam turbine and associated piping? From detailed
research* some of the pipes serve only to make loud and
tactically inconvenient whooshing noises as they leak
steam at inopportune moments. At least until Kowalski
closes some valve or other. We can eliminate steam by
going with Sterling engines and/or thermoelectric
generators. We can also eliminate the troublesome reactor
by making the submarine a large Radioisotope Thermal
There's two good candidates, Strontium 90 and plutonium
238. At ~0.5W/g you'd need 1.0x10^9 grams, or 1000
metric tons. That's chump change in a marine environment.
Ballistic missile subs are 15-50,000 tons. Even the volume
is very manageable, 1000 tons of plutonium is 55m^3 It's a
Admittedly, the arrangement of plutonium is somewhat...
critical. It might be wise to use a mix of Pu/Sr and lay the
material out along the full length of the keel. Heat
transmission to the Stirling engines and thermoelectric
generators could be achieved with heat pipes and heat
storage in phase change materials could allow for varied
power delivery and perhaps a smaller mass of material.
While steam turbines are ~35% efficient, compared to the
~10% of thermoelectric generators, they're solid state and
therefore silent. They don't need generators with
associated losses and noise. Sterling engines can be 50%
efficient and have been demonstrated in submarines. So a
mix of the two could easily equal traditional drive
efficiency with fewer moving parts. If things get desperate,
then you could easily hot-rod your submarine with
Polonium 210, 280 fold more power per unit volume,
although you'll need to refuel every few months.
Supplementary benefits include being able to say "we've
moved away from lagacy fission reactors in our strategic
submarine fleet" which will keep the CND lot happy.
Meanwhile, the subs can be tooling around under the
icecap, clearly demonstrating nuclear-powered
performance. A wink and a nod from the right ambassador
and before you know it the Chinese think you've cracked
*I watched several movies
Radioisotope Thermoelectric Generators
[bs0u0155, May 06 2019]
Sterling Engine submarine propulsion
[bs0u0155, May 06 2019]
[bs0u0155, May 06 2019]
The World's Worst Warships
Disquieting. [8th of 7, May 07 2019]
||We regret to inform you that while this is a good idea, you are a little behind the curve; however, that's entirely excusable as while USVs powered by RTGs are Baked, they are definitely not WKTE.
||We could tell you more, but then we'd have to kill you.Well, we wouldn't exactly have to, but we would do it anyway just for the look of the thing.
||[suggested-for-deletion], not an innovation.
||Surely these days you can run a submarine off a USB port?
||Quite a few submarines run out of USA ports, but that's not quite the same.
||Guessed it would be an RTG as soon as I read the subtitle.
||Wikipedia says Gotland-class submarines can generate power while submerged, without consuming air, by using their Stirling engines. But it doesn't say what the heat source is. I don't see how it could be combustion of diesel.
||They use HTP. They bought the design of the RN's "Fancy" torpedo (c.f. HMS Sidon) and evolved it into AIP, far better than the WW2-era Kreislauf sysrem developed by the Kriegsmarine (and subsequently by the Ivans).
||I never heard of power over HTTP - I presume it's the modern day equivalent of powering an old telephone handset over the telephone cables?
||Hang on. Stirling, thermoelectric... all too complicated.
||Nuclear stuff needs cooling, right? So, why faff around
extracting heat only to turn it into electricity to turn a
propeller to push the sub along? Just let water in the front
end, squirt superheated steam out the back end, and you're
good to go.
||Better yet still - you could squirt 90% of the steam out the
back, and the other 10% out of an annulus near the nose, to
give a cavitating submarine capable of a few hundred knots.
||... and easy meat for the first acoustic torpedo that happens along.
||That sort of propulsion isn't exactly stealthy.
Stealth is an important thing for subs ...
||Only because they don't have speed. When you're
supercavitating at 300mph I think you'll be happy to let
||//When you're supercavitating at 300mph I think you'll be
happy to let everyone know.//
||I wonder what the energy requirements for that would be?
Also I think the supercavitating would generate a couple of
minor issues, the sonar operator might mention some issues
with a high noise floor. Any failure in the supercavitation
machinery would result in the sort of deceleration
experienced by pilots flying into cumulo granite formations.
||//deceleration// So, crumple zones, then. Maybe one of
those collapsible steering wheels.
||It might work well for surface vessels, but nuclear-powered
surface vessels tend to be aircraft carriers, and those can't
move very fast without failing at their stated purpose.
||I'd've thought a fast-moving aircraft carrier would make it
easier to take off and land. If you can get up to 150 knots you
could operate A380s, which would be pretty intimidating.
||//you could operate A380s, which would be pretty
||Oooooh, gin soaked business class passengers. Scary. I'll take
a B52 with a mix of AMRAAMs, anti-ship, anti-submarine and
||This is why the 2nd Amendment was intended to
recognize every red-blooded American's God-given
right to build defensive lighthouses on their property.
A lighthouse with space-age technology (e.g. lasers
illuminating the land for miles around) and
maaaaaaybe some defensive plutonium tucked
away somewhere sounds like a croissant tier idea.
Build a moat around it and call it a submarine.