09V/09VI (095/096) Nuclear Submarine Thread

[Anlsvrthng]

Unsurprisingly, Metallurgy again dictates Hull strength and therefore Max dive depth of the Submarines.

Please, Log in or Register to view URLs content!

Japan, Germany and US continue to remain at the forefront of this (obviously). Russia sidestepped (kind of) by application of its vaunted Titanium reserves.

But is Mariana trench the limit for deep diving?
Other than the Hull strength (dictated by metallurgical progress), there is another factor that might (? When factoring in the costs sunk on the Metallurgy and manufacture of a submarine) prevent nations from demanding that Submarines dive deeper. The SOFAR channel.

Please, Log in or Register to view URLs content!

Please, Log in or Register to view URLs content!

The SOFAR channel is a particular depth at which sound is able to propagate at great lengths (because of the conflux of certain factors like pressure, temperature and salinity which in turn affects sound wave propagation). Usually it's about 600 to 1000 m depths.

Metallurgy gives the maximum weight budget for given delta pressure and given buoyancy for all non pressure vessel equipment.


The relationship between the diving deep at constant pressure vessel mass given by the specific strength of the given wall material.

Now, the rules can be cheated by :
1. automate as many system as possible, and pressurise the non human occupied segments with helium , with half strength vessel wall compared to the target diving deep. Means if the 25% of ship is atmospheric, then the pressure full vessel wight can be decreased by 40% . Problem it require lot of automation, like on the Russian submarines.
2. Pressurise the whole ship. With nuclear propulsion it is not a big deal, and can give few hundred extra meters of diving deep. Problem is the crew can't escape the ship by surfacing and moving to inflatable boards - it require pressurised escape crew capsule, like on the Russian /Soviet attack submarines .
3. Use high tensile strength pressurised carbon fibre tanks to get extra buoyancy , but it means of course if the extra tank damaged then the ship sink like a stone.


Above can increase dramatically the diving deep, but of course it complicate the design and makes it very expensive.

 

[hkky]

This nuclear reactor has passive circulation features but for a civilian one, the passive or natural circulation is required essential if not by regulation in case if active cooling systems fail. I might speculate that the nuclear reactor for the 095 and 096, as well as future Chinese CV-N maybe based on this reactor. They plan to use it for floating or ship type nuclear power plants.

View attachment 62759View attachment 62760View attachment 62761View attachment 62762View attachment 62763

I think we should not get ahead of our selves here on the passive cooling. It states passive cooling in case of transients and design basis accidents. Under these conditions you'd be worried about keeping the reactor from overheating/melting rather than generating power (under this condition, we'd be looking at handling a maximum of 7% power and decreases exponentially with time}. This feature is available in all pressurized water reactors, as long as there is cooling water in the steam generator and the reactor has sufficient decay heat to create the thermal condition for natural circulation. This type of power plants uses lowly enriched uranium and need refueling frequently, a feature I don't think you'd want in a naval reactor. Core design and size using highly enriched uranium in a naval reactor would be quite different and the ability for natural circulation would be dictated by the space available. Also remember commercial power plants are designed to maximize power output and push design/material performance to the limit. Naval reactor design should not have this constraint under normal operating conditions.

 

[Orthan]

Overall China's reactor tech is quite advanced. They have a strong part in the UK's Hinkley nuclear power plant under construction and has partnership with the Saudis.

Well this is an article from national interest. It says that civilian nuclear tech its not very useful for nuclear submarines. If so, what is the level of china´s submarine nuclear reactor?

Please, Log in or Register to view URLs content!

 

[Figaro]

Well this is an article from national interest

The real question you should be asking is why are you getting information from the National Interest and not from much more credible sources.

 

[Hendrik_2000]

Well this is an article from national interest. It says that civilian nuclear tech its not very useful for nuclear submarines. If so, what is the level of china´s submarine nuclear reactor?

Please, Log in or Register to view URLs content!

I don't know if you can trust Dave Majumdar He is known China basher for obvious reason. The article is from 2015 and TNI no the most rusted site
China can built quiet submarine like Song and Yuan And china nuclear reactor technology is quite advance witness the civilian reactor. China is self sufficient in reactor supply line
But complete black out when it come to military nuclear technology

 

[hkky]

China has purchased almost every type of commercial pressurized water reactor designs (CANDU, VVER, French 900 MWe, EPR, AP1000, etc) in the world and has been operating them for a while. They have started to build plants with their own specs in recent years (like how the French modeled their plants based on Westinghouse design so many years ago), but they are still behind. The advantage China has now in commercial space is the experience in building new plants, close to budget and schedule than western companies. It pains me to say, after regular interactions with all 3 major nuclear utilities in China the last 10 years, they are way behind in experience. They appear to be isolated and still digesting technical manual material without too much experimentation/exploration of their own. I do not know if this is a an artifact of the system or conservative culture. After so many plants built in the last 10 years I'd hope there is enough critical mass to take off soon, like how Korea has in people and tech development.

 

[Dante80]

Generally speaking, large civilian power generating reactors are not very helpfull in bringing the TRL of marine military reactors up. The requirements of operation (from ramping up to environment to control) are competely different, to the point where in many subsystems there is zero relevance.

This might sound counter-intuitive for some, but it is simply how things work. Now, as far as China is concerned, we really have no concrete idea about where they are in marine reactor TRLs. As you know, the whole thing is unsurprisingly shrouded in secrecy, so it would be difficult to even attempt an educated guess.

 

[hkky]

Generally speaking, large civilian power generating reactors are not very helpfull in bringing the TRL of marine military reactors up. The requirements of operation (from ramping up to environment to control) are competely different, to the point where in many subsystems there is zero relevance.

This might sound counter-intuitive for some, but it is simply how things work. Now, as far as China is concerned, we really have no concrete idea about where they are in marine reactor TRLs. As you know, the whole thing is unsurprisingly shrouded in secrecy, so it would be difficult to even attempt an educated guess.

I would not say they could not support each other. The physics is pretty much the same, implementation is different. There are many people from the navy side move to the commercial side, in both operation and design, without too much difficulty. Bottom line is if you have the expertise, it could be used by either side.

 

[Orthan]

I don't know if you can trust Dave Majumdar He is known China basher for obvious reason.

Actually, the part about the submarine nuclear reactor tech came from Andrew Ericsson.

But complete black out when it come to military nuclear technology

Now, as far as China is concerned, we really have no concrete idea about where they are in marine reactor TRLs.

So, we are in the dark regarding this. My guess is, i doubt that they can approach even the russian tech right now, since they cant import nuclear subs, and the US and russia have much more experience in building nuclear subs.

 

[azesus]

Orthan keyboard Einstein he can measure technological progress in his mind, experience means squat we dont get light bulbs from gradually improving candles or get automobiles by gradually improving horse carriages