Chinese Marine Propulsion

bsdnf

Senior Member
Registered Member
so this has already been discussed, but I wonder if super supercritical carbon dioxide technology already made its way into 095?

Please, Log in or Register to view URLs content!

I'm not sure about dimension of MSR or Supercritical CO2 tech, but if you can fit this into 095, it just kills steam turbine in efficiency and probably noise level.

Here is an AI generated summary from that video from a while back.

There is much we don't know, but if they actually managed to get this to work in a nuclear icebreaker, I see no reason why it cannot be put into 095 or 096.
The first commercial supercritical carbon dioxide generator set just went into operation on December 31st last year.

They need to verify its durability here (supercritical carbon dioxide is corrosive to pipes), then apply it to a completely new nuclear reactor design and verify it accordingly, and finally convert it into a marine reactor. All of these will take a long time.

Another, more short-term and gradual approach is to maintain the design decoupling of the generator set and nuclear reactor, just changing the generator design. However, this would still require testing on a generation of ships.

Of course, the benefits are also obvious. Supercritical carbon dioxide generator sets can generate 20~30% more power, have a ~50% smaller size and way fewer pipes and valves compared to steam turbines, which is a very important feature for ships, especially submarines.

In the case of a completely new design for nuclear reactor coupling, it will be even more efficient, and automatically shut down the reactor when it malfunctions.
 
Last edited:

BoraTas

Major
Registered Member
I was researching for the last few days. It seems FSRs and MSRs make a dream team with the sCO2 turbines. PWRs are unfortunately too cold for an efficient sCO2 turbine system at 300-325 degrees Celcius. Especially FSR + sCO2 is a monster combo. Fast sodium reactors (FSR) need no pressure shell. They are lighter than PWRs at the same output. They are also hotter by ~200 Celcius. That is enough for an efficient sCO2 system. Even if steam is used, the increased temperature increases the efficiency. Another benefit of FSR and sCO2 combo is sodium-water explosion risk is eliminated.
 

mister unknown

New Member
Registered Member
I was researching for the last few days. It seems FSRs and MSRs make a dream team with the sCO2 turbines. PWRs are unfortunately too cold for an efficient sCO2 turbine system at 300-325 degrees Celcius. Especially FSR + sCO2 is a monster combo. Fast sodium reactors (FSR) need no pressure shell. They are lighter than PWRs at the same output. They are also hotter by ~200 Celcius. That is enough for an efficient sCO2 system. Even if steam is used, the increased temperature increases the efficiency. Another benefit of FSR and sCO2 combo is sodium-water explosion risk is eliminated.

That certainly sounds like compelling enough tech to build the later variants on. That said, MSR is probably a relatively better tech on an SSN than FSR right? I know I wouldn't want a generator that explodes if it touches water on any kind of naval vessel, no matter how well contained it is.

In any case - MSR + SCO2 + rimless pumpjet propulsion: THAT would be a hell of a combo. Granted the PLAN will never be risk tolerant enough to put all that new tech into the next follow on model, but hopefully they get separately tested in other platforms soon enough so that they can be integrated into future ships of this class.
 
Last edited:

Tomboy

Captain
Registered Member
In any case - MSR + SCO2 + rimless pumpjet propulsion: THAT would be a hell of a combo. Granted the PLAN will never be risk tolerant enough to put all that new tech into the next follow on model, but hopefully they get separately tested in other platforms soon enough so that they can be integrated into future ships of this class.
Given that the best rimdrives are like 3MW in power and have cooling issues when scaling up further with current technology. A 38+ MW rimdrive will take atleast a decade optimistically to even become possible. sCO2 was just demonstrated late last year on a non nuclear heat source, demonstrating it coupled to a reactor will take a few more years before you can even think about trying to put it into a submarine.

These speculations are overly excessive IMO and even thinking some of these feature might even make it into subsequent 09V models is stretching it. Maybe 09VII will feature most if all of these feature when it comes along in the late 30s or even early 40s or atleast a very late block 09V optimistically.
 

mister unknown

New Member
Registered Member
Given that the best rimdrives are like 3MW in power and have cooling issues when scaling up further with current technology. A 38+ MW rimdrive will take atleast a decade optimistically to even become possible. sCO2 was just demonstrated late last year on a non nuclear heat source, demonstrating it coupled to a reactor will take a few more years before you can even think about trying to put it into a submarine.

These speculations are overly excessive IMO and even thinking some of these feature might even make it into subsequent 09V models is stretching it. Maybe 09VII will feature most if all of these feature when it comes along in the late 30s or even early 40s or atleast a very late block 09V optimistically.
Yes, I know it's just daydreaming for now. All these sub systems will probably separately show up in small UUVs to be tested before it shows up elsewhere.
 

Blitzo

General
Staff member
Super Moderator
Registered Member
what gets used in the initial boat and what gets used on future variant are entirely different issues.

The difference between initial 093 and 09IIIB is Oberon class to late LA class.

Even more, 09VI has no information yet.

To be fair your prior post in 1828 did say "but I wonder if super supercritical carbon dioxide technology already made its way into 095" which does suggest a meaning of asking whether it's "already implemented".

I agree it's possible future variants may utilise significant new technologies, but in absence of credible rumours alluding to it, we can't fairly speculate too much.
 
Last edited:

tphuang

General
Staff member
Super Moderator
VIP Professional
Registered Member
Given that the best rimdrives are like 3MW in power and have cooling issues when scaling up further with current technology. A 38+ MW rimdrive will take atleast a decade optimistically to even become possible. sCO2 was just demonstrated late last year on a non nuclear heat source, demonstrating it coupled to a reactor will take a few more years before you can even think about trying to put it into a submarine.

These speculations are overly excessive IMO and even thinking some of these feature might even make it into subsequent 09V models is stretching it. Maybe 09VII will feature most if all of these feature when it comes along in the late 30s or even early 40s or atleast a very late block 09V optimistically.
by the way, if you look at the evolution of 09III class, I'm not sure if they will ever have 09VII. At this point, USN could also have 40 years of Virginia class construction.
 

charles18

Junior Member
Registered Member
I was researching for the last few days. It seems FSRs and MSRs make a dream team with the sCO2 turbines. PWRs are unfortunately too cold for an efficient sCO2 turbine system at 300-325 degrees Celcius. Especially FSR + sCO2 is a monster combo. Fast sodium reactors (FSR) need no pressure shell. ...
Sodium cooled reactors are a BAD choice for marine applications.
Sodium is highly chemically reactive when exposed to water.
Please, Log in or Register to view URLs content!
 

plawolf

Lieutenant General
Given that the best rimdrives are like 3MW in power and have cooling issues when scaling up further with current technology. A 38+ MW rimdrive will take atleast a decade optimistically to even become possible. sCO2 was just demonstrated late last year on a non nuclear heat source, demonstrating it coupled to a reactor will take a few more years before you can even think about trying to put it into a submarine.

These speculations are overly excessive IMO and even thinking some of these feature might even make it into subsequent 09V models is stretching it. Maybe 09VII will feature most if all of these feature when it comes along in the late 30s or even early 40s or atleast a very late block 09V optimistically.

Your entire timeline is based on the assumption that the sCo2 reactor at the steel mill is the first experimental demo unit. But the way it was disclosed very much suggests otherwise. There wasn’t much fanfare about it being built and first put into operation as you would expect from a pioneering, revolutionary tech demonstration. Instead it’s just there, doing it’s thing like it’s just a regular Tuesday.

What seems more likely given the evidence so far is that sCo2 reactors were pioneered in secret and the steel mill application is just the commercialisation of it. And if you look back in recent history, that’s how things generally went. Apple didn’t pioneer any of the 10 key technologies needed to make the iPhone. Military research projects did the heavy lifting on pioneering and implementing those technologies, while Apple just took the end products of those military research projects, fine tuned it and combined it into the iPhone.

I would say it’s entirely possible that sCo2 reactors were first developed for the PLAN submarine programmes, and the steel plant reactor and planned icebreakers are just the commercialisation of that technology, rather then it being the other way around, that private industry fronted the developmental costs of making this thing work and the navy came sniffing around for its naval applications after the fact. In fact, I would say the balance of probabilities makes it far more likely that the navy developed the tech first as opposed to the other way around. Because if some private entity did indeed pioneer this tech, why the hell are they not shouting it from the rooftops and promoting it everywhere to start recouping some of that massive capital and development costs this would have taken?

If you broaden your prospects to consider the possibility that just because we found out about the commercial use of a sCo2 reactor first doesn’t mean that sCo2 reactors were first pioneered for commercial use and suddenly the possibility of it being used on the 09doesn’t seem so remote at all.

It would not be outside the realm of possibility that the 09V might not even be using the first gen sCo2 naval nuclear reactor, as it would have made far more sense to first validate the tech in a custom built 09III or SSK hull first. Indeed, it’s actually possible that the 09IIIB might be the first user of sCo2 reactors given the kind of delay you would expect before the fruits of cutting edge military R&D get’s declassified enough for commercial applications.

Indeed, I would say that the 09IIIB class, or at a minimum a test boat from the class running sCo2 is probably a prerequisite to the 09V running it, as the project management risks would be too great to incorporate it into the 09V design at inception if that was not the came.
 

mister unknown

New Member
Registered Member
Your entire timeline is based on the assumption that the sCo2 reactor at the steel mill is the first experimental demo unit. But the way it was disclosed very much suggests otherwise. There wasn’t much fanfare about it being built and first put into operation as you would expect from a pioneering, revolutionary tech demonstration. Instead it’s just there, doing it’s thing like it’s just a regular Tuesday.

What seems more likely given the evidence so far is that sCo2 reactors were pioneered in secret and the steel mill application is just the commercialisation of it. And if you look back in recent history, that’s how things generally went. Apple didn’t pioneer any of the 10 key technologies needed to make the iPhone. Military research projects did the heavy lifting on pioneering and implementing those technologies, while Apple just took the end products of those military research projects, fine tuned it and combined it into the iPhone.

I would say it’s entirely possible that sCo2 reactors were first developed for the PLAN submarine programmes, and the steel plant reactor and planned icebreakers are just the commercialisation of that technology, rather then it being the other way around, that private industry fronted the developmental costs of making this thing work and the navy came sniffing around for its naval applications after the fact. In fact, I would say the balance of probabilities makes it far more likely that the navy developed the tech first as opposed to the other way around. Because if some private entity did indeed pioneer this tech, why the hell are they not shouting it from the rooftops and promoting it everywhere to start recouping some of that massive capital and development costs this would have taken?

If you broaden your prospects to consider the possibility that just because we found out about the commercial use of a sCo2 reactor first doesn’t mean that sCo2 reactors were first pioneered for commercial use and suddenly the possibility of it being used on the 09doesn’t seem so remote at all.

It would not be outside the realm of possibility that the 09V might not even be using the first gen sCo2 naval nuclear reactor, as it would have made far more sense to first validate the tech in a custom built 09III or SSK hull first. Indeed, it’s actually possible that the 09IIIB might be the first user of sCo2 reactors given the kind of delay you would expect before the fruits of cutting edge military R&D get’s declassified enough for commercial applications.

Indeed, I would say that the 09IIIB class, or at a minimum a test boat from the class running sCo2 is probably a prerequisite to the 09V running it, as the project management risks would be too great to incorporate it into the 09V design at inception if that was not the came.
It's also possible to test sCo2 tech on SSKs right? Granted the tech would be an optimal complement for nuclear power generation, but an SSK could also potentially be used as early-stage testbeds right?
 
Top