They are probably referring to the model of a concept submarine which would use magnetic propulsion. They are jumping the gun if they think China had already made the break through, when that thing is still in the concept stage.
Ideal PLAN submarine
- Thread starter crobato
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They are probably referring to the model of a concept submarine which would use magnetic propulsion. They are jumping the gun if they think China had already made the break through, when that thing is still in the concept stage.
Pointblank
Senior Member
The Japs tried this concept before; it didn't exactly work. First off, the ship was slow, there was extensive cavitation, which caused noise, and it requires a lot of power (which creates a loud plant noise). Not something you want in a submarine.
The captions under the picture suggest a nuclear submarine rather than a conventional one. Its not really clear if this is referring to as MHD meaning MHD propulsion, or MHD as in direct electrical generation from a nuclear reactor, both of whom would be radical in terms of submarine propulsion.
By the way, in the course of research I found out that MHD power generation is also possible using fossil fuels, thereby cutting out the mechanical dynamo out of the electrical production process.
Now to another topic, the now not so top secret Russian Savros submarine with the "revolutionary" nuclear plant. At 3950mt, the thing is still huge compared to the smallest Soviet Union nuclear sub, the Alfa class, which comes in at roughly 2500mt surfaced. The Alfa class is noted for using lead cooled nuclear reactors.
While lead sounds toxic, it does have certain safety benefits. First, such a reactor doesn't blow up thanks to liquid lead unlike pressurized steam. It immedietly cools and hardens. Lead by its atomic density also blocks and controls radiation. By virtue of its density, it captures and retains heat much better than water. It also has a very high thermal efficiency and conduction, which means that such a reactor system can be made much smaller than a PWR.
Despite the immaturity of such technology, the lead reactors of the Alfas did work. And compared to the other Soviet nuclear subs, they came off with a rather surprisingly better safety record. The catch is that once the coolant cools to a solid state, its a pain to heat it back to liquid again, and the failure to do so, can write off the sub. In fact, four of the Alfas became useless that way. In hindsight, the technology was successful, the logistics wasn't. The subs have to run their reactors non stop even at port, and when they're finally spent, they're spent. At that time the idea of "disposable" reactors wasn't acceptable, but can such an idea be acceptable now?
Now to another topic, the now not so top secret Russian Savros submarine with the "revolutionary" nuclear plant. At 3950mt, the thing is still huge compared to the smallest Soviet Union nuclear sub, the Alfa class, which comes in at roughly 2500mt surfaced. The Alfa class is noted for using lead cooled nuclear reactors.
While lead sounds toxic, it does have certain safety benefits. First, such a reactor doesn't blow up thanks to liquid lead unlike pressurized steam. It immedietly cools and hardens. Lead by its atomic density also blocks and controls radiation. By virtue of its density, it captures and retains heat much better than water. It also has a very high thermal efficiency and conduction, which means that such a reactor system can be made much smaller than a PWR.
Despite the immaturity of such technology, the lead reactors of the Alfas did work. And compared to the other Soviet nuclear subs, they came off with a rather surprisingly better safety record. The catch is that once the coolant cools to a solid state, its a pain to heat it back to liquid again, and the failure to do so, can write off the sub. In fact, four of the Alfas became useless that way. In hindsight, the technology was successful, the logistics wasn't. The subs have to run their reactors non stop even at port, and when they're finally spent, they're spent. At that time the idea of "disposable" reactors wasn't acceptable, but can such an idea be acceptable now?
Planeman, that supercavitating idea of yours using a DF-21 gave me some idea how a ballistic antiship missile may work.
What if for example, you make the entire second stage of the SLBM, work like a rocket propelled supercavitating torpedo like a Skval. The upper stage of the missile is directed and plunged into the water with last moment air braking to slow down the descent. In effect, its like a giant ASROC built like a ballistic missile and carrying a Skval type torpedo.
What if for example, you make the entire second stage of the SLBM, work like a rocket propelled supercavitating torpedo like a Skval. The upper stage of the missile is directed and plunged into the water with last moment air braking to slow down the descent. In effect, its like a giant ASROC built like a ballistic missile and carrying a Skval type torpedo.
Since the skval alone weights 2.700kg, I guess that would be a really heavy SSM, especially if you want it to have a usefull range. So I think a ballistic version may be more practical.
However, I think you will need a target-info update just before the skval fires in the water. That means an accoustic array and software, or an uplink on the torpedo.
Err, what is turbo-electric drive and Azipod?
But here is my preliminary SSN design.
I like the Alfa, but I don't really know much of its hull.
What I put on my sub was a sharper (ball point pen front-like) bow and instead of a ducted fan, I gave the sub intakes for water to cool and at the same time propell the sub and leave space for a stern sonar. Whether the stern is a sound magnet or mute, I hope the "Orca holes" doesn't bring forth the former.
Bridge is pretty much Alfa shaped.
And if the driving surfaces look a little off center, I based them on those in Dolphins and Mako Sharks, just an idea.
For the lead coolant problem above, would it be a good idea to have a lead reactor AND a HTGR(this being the heater) onboard?
But here is my preliminary SSN design.
I like the Alfa, but I don't really know much of its hull.
What I put on my sub was a sharper (ball point pen front-like) bow and instead of a ducted fan, I gave the sub intakes for water to cool and at the same time propell the sub and leave space for a stern sonar. Whether the stern is a sound magnet or mute, I hope the "Orca holes" doesn't bring forth the former.
Bridge is pretty much Alfa shaped.
And if the driving surfaces look a little off center, I based them on those in Dolphins and Mako Sharks, just an idea.
For the lead coolant problem above, would it be a good idea to have a lead reactor AND a HTGR(this being the heater) onboard?
I think the Alfa is shaped like an albacore. The hydrodynamic design is quite advanced, with the flaring and integration of the sail to the hull that you will only see in subs much later like the Type 212.
I think HTGR and lead bisimuth cooling are incompatible because they represent two forms of reactor heat transfer systems. You only use one or the other. The main problems of lead reactors is corrosion, which the Russians did manage to solve, and the heating of the coolant, which they didn't, but deserve a new round. I am guessing that the Sarov submarine might be the Russian's second take on a lead bismuth reactor submarine.
Turbine electric means that the propeller is not shafted to the turbine directly. It means the turbine drives a generator instead, which then drives an electric motor. There are pros and cons to this. Pro reasons include the submarine is decoupled from the engine, which means you can make reactor and turbine changes without affecting the rest of the sub, allowing for a more modular layout and which makes it great for developmental subs. If you remove the need for reduction gears, it can also be quieter. The con is greater magnetic detection which is always an issue when you use big electric motors, like in diesel electric subs. Also added weight and space, due to the electric motor.
Here is a little tidbit. Do you know that deep underwater, nuclear submarines sometimes have a strange glow in the hull? That is due to the radiation from the reactor.
I think HTGR and lead bisimuth cooling are incompatible because they represent two forms of reactor heat transfer systems. You only use one or the other. The main problems of lead reactors is corrosion, which the Russians did manage to solve, and the heating of the coolant, which they didn't, but deserve a new round. I am guessing that the Sarov submarine might be the Russian's second take on a lead bismuth reactor submarine.
Turbine electric means that the propeller is not shafted to the turbine directly. It means the turbine drives a generator instead, which then drives an electric motor. There are pros and cons to this. Pro reasons include the submarine is decoupled from the engine, which means you can make reactor and turbine changes without affecting the rest of the sub, allowing for a more modular layout and which makes it great for developmental subs. If you remove the need for reduction gears, it can also be quieter. The con is greater magnetic detection which is always an issue when you use big electric motors, like in diesel electric subs. Also added weight and space, due to the electric motor.
Here is a little tidbit. Do you know that deep underwater, nuclear submarines sometimes have a strange glow in the hull? That is due to the radiation from the reactor.