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Japan's Silent Submarines Extend Range With Lithium-Ion Batteries (nikkei.com)
AmiMoJo shares a report from Nikkei Asian Review: Japan's first submarine powered by lithium-ion batteries was launched on Thursday. The [Soryu-class diesel-electric] submarine can reach speeds of roughly 20 knots and displaces 2,950 tons. It will be delivered to the Japan Maritime Self-Defense Force in March 2020. Batteries are recharged by the energy generated by Oryu's diesel engines. The vessel switches to batteries during operations and actual combat in order to silence the engines and become harder to detect. The lithium-ion batteries radically extend the sub's range and time it can spend underwater.
Plus, when they run out of charge, they double as torpedoes.
If you like half the total energy efficiency and a fraction of the energy storage capacity compared to diesel/lithium ion combo then, yeah...way better!
I don't always use unix-like operating systems; but when I do, I prefer FreeBSD.
If you like half the total energy efficiency and a fraction of the energy storage capacity compared to diesel/lithium ion combo then, yeah...way better!
Nuclear for the win
Pain is merely failure leaving the body
... out on the Big Pond.
Aviation Anti-Submarine Warfare Technician 2nd class.
The other side of the story is using hydrophones (waterproof microphones) to listen to the deep.
Every major country has these permanent stations anchored out across the oceans.
An audio spectrum analyzer sweeps the apparently random noise with tones from near zero up to the khz.
Obviously, when noise from the sea is the same frequency as the artificial pure tone, they are added together.
Rinse, repeat.
The results are charted with frequency on the X axis and amplitude on the Y.
A computer alerts when it sees a straight line, created over time.
That's the tone and sea noise agreeing when they coincide with the sounds of reefers (ice boxes), generators, prop cavitation, screw bearings, engine noises, and miscellaneous unwanted fingerprints.
We could tell you the fucking captain's name by the signature.
Aircraft drop sonobouys to do the same.
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Then there's this:
Submarines, to date, have a lot of fucking metal that distorts the Earth's magnetic field locally.
Permanent or airborne magnetometers can pick up these small anomalies.
Sunken ships have long been logged and they don't move.
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Then, there are active sonar devices, permanent or airborne (tethered from helicopters) that map the surroundings and alarm on novel or moving objects.
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The submarine/anti-submarine balance of technology is similar to the battle of virus/antivirus one.
This latest improvement by the Japanese may or may not be better than existing or future state of the art detection.
It little behooves the best of us to comment on the rest of us.
I guess you never heard of the snorkel?
If you like half the total energy efficiency and a fraction of the energy storage capacity compared to diesel/lithium ion combo then, yeah...way better!
Nuclear for the win
Only if you need to go far and or fast while you're submerged.
And nukes are much harder and more expensive to make quiet, and even then they'll never be as quiet as a sub running on batteries. You know how much noise a sub's batteries make? Go outside and try to hear your car's battery.
For defensive purposes, conventional subs are hard to beat.
I could have written "submerged below snorkel depth" but I assumed an intelligent reader. More to the point, I erred in claiming that WW II submarines were not actually diesel-electric. They actually were.
When all you have is a hammer, every problem starts to look like a thumb.
The cells are sealed, you can throw those li-ion straight into the chuck and they just sink. Currently gaining a lot of traction as marine batteries, the only issue is the price.
When all you have is a hammer, every problem starts to look like a thumb.
Kamikaze tactics had nothing to do with submarines.
Yes they did: Kaiten suicide subs.
https://en.wikipedia.org/wiki/...
German Type 212 up to 3 weeks of silent running on fuel cells.
By the time a warhead gets inside your submarine you have far bigger issues than exploding batteries, if they even do.
When all you have is a hammer, every problem starts to look like a thumb.
Nuclear also has it's issues. A diesel electric sub is much quieter, and therefore harder to detect, than a nuclear as long as the diesel electric is running in electric mode. The trade-off is that when running the diesel it's much, much, louder, and the all electric range tends to be limited. Nuclear allows longer range and relative quiet, but not as quiet as electric.
This is interesting because it extends that electric range, and therefore extends the advantage over nuclear in short term engagements.
Subs running on batteries still drive propellers that create noise. It's not the power source of a sub that is most important it is the advanced sensor suites capable of hearing a dolphin fart 100 miles away that makes it dangerous. There are no great technological secrets involved with building a modern day sub. Specs on everything from power sources to composite hull materials are available to anyone. The specs for the sensor suites and targeting systems are not so readily available. For a lot of countries costs determines what type of sub they build but countries such as the US have never shied away from developing cutting edge military technology regardless of how much it costs.
Not quite.
The 5th Basic Energy Plan, approved in July 2018, maintains the same electricity percentages as agreed in mid-2015. It presents nuclear power as âoean important base-load power source contributing to the stability of the long-term energy supply-and-demand structure,â and states that necessary measures will be taken to achieve nuclear powerâ(TM)s share of 20-22% in the 2030 energy mix.
http://www.world-nuclear.org/i...
Japan shutdown all nuclear power plants for reviews on safety after the tsunami hit Fukushima. Since then Japan has declared many of the smaller and older plants unfit for restart, a few newer reactors have already been restarted, and about half of their nuclear power plant fleet is set to be restarted soon, and they have plans for the construction of new nuclear power plants. To get from near 0% to 20% nuclear in little over a decade means they intend to be very aggressive in refits on existing nuclear power and in construction of new nuclear power.
Japan has been restricted by their post-WWII constitution from having any military other than a small self defense force. An air force and/or navy capable of acting beyond territorial waters was barred to them as a condition of surrender, and today is considered provocative by their neighbors. Recent events has made Japan quite willing to build up a very real military, as well as the USA willing to give them the freedom to do so. World War II was a long time ago, and even memories of Fukushima are fading fast, given more pressing matters on energy policy and international politics.
I would not be surprised if Japan acquires nuclear submarines soon.
I am armed because I am free. I am free because I am armed.
No, you really need to tell them about how much more fragile their battery casings are than they really think. Don't hold back.
When all you have is a hammer, every problem starts to look like a thumb.
If you like half the total energy efficiency and a fraction of the energy storage capacity compared to diesel/lithium ion combo then, yeah...way better!
Nuclear for the win
A diesel on batteries can be quieter ... slightly. (The nuke plant coolant system and the steam system must always run.) But the diesel can't be on batteries forever.
Pros and cons, pros and cons ...
Noise isn't necessarily the problem with nuclear reactors, it's the heat. They dump a bunch of heat into the water, which can be picked up by satellites. They have to go *deep* to evade detection this way, which limits where they can go. You won't be able to tell *exactly* where the sub is, but you get the idea that one is in the area, and it's general direction.
My Other Computer Is A Data General Nova III.
Subs running on batteries can turn off propellers. Nuclear subs always run cooling.
I enirely agree about diesel electric subs by the way. And about nuclear ones.
They also in practice require a nuclear weapons program to produce the fuel.
This is Japan we're talking about. At any given point in time they're probably about 6 months to a year away from having nuclear tipped ICBMs, should they so choose.
They've got a large, active nuclear industry including reprocessing and uranium enrichment for their reactors.
Also, they have probably the world's current best solid fuel rocket. If you can reliably places catellites in low earth orbit, geosynchronus orbit or sun synchronus orbit, then you can easily hit any point on Earth.
They have the education level, tech level, supercomputing expertise and manufacturing prowess to produce them.
SJW n. One who posts facts.