Nuclear power in Russian ships

With electric drive you could use a small nuclear power generator whose primary role might just be keeping the batteries topped up and to boost speed.

You could have multiple nuclear power plants throughout the ship... it does not need to be centralised, and would be better for battle damage resistance if they were widely separated.

Being able to hold station precisely and to manouver in tight quarters is useful for any sized ship, but more so large ships.

US and Norwegian experience with civilian ships suggests that even at night collisions are an issue... being able to rapidly stop and move sideways would be invaluable... and being able to manouver precisely means you could sail in to places other ships couldn't follow you...

It has close to 200 MW shaft power, means with a podded full electric propulsion it would nee 2000-3000 tons of electrical motors.

I doubt they have motors of that weight, but more importantly have never tried to make electric motors for ships of that size and weight.

Actually making ships that size and weight will mean work will be done to reduce weight and size and improve performance.

You sound like PD saying EM cats are a waste of time and money, yet the reasons for making catapults using EM instead of steam are pretty clear, and the technology and materials needed to make them efficient would also be very valuable in an all electric drive ship propulsion system.

If they can get them working well it has enormous growth potential and enormous performance potential that will make ships safer and faster and much more manouverable even if it just has two podded electric motors at the front that can angle down to lift the hull in high forward speeds with the rear props fixed like traditional props for forward propulsion and high speed...

Singular_Transform wrote:

mnztr wrote:Ships need eletricity anyway, and more and more of it. I am not sure what a COGOG gearbox weighs but it can't be light. Also with an effcient electric drive you can carry less fuel.

Let check the Ford carrier example.

It has close to 200 MW shaft power, means with a podded full electric propulsion it would nee 2000-3000 tons of electrical motors.

It could increase the ship weight by 2-3%, and what savings are on the other side ?


And the Ford actually has 200 MW generating capacity, because the high RPM generators weight so small it doesn't affect the ship weight  by measurable ways.

The Ford has about 260K hp but AZIpods are super efficient, just 60MW with 3 Azipods can move this behemoth at 25Knots:

https://en.wikipedia.org/wiki/Harmony_of_the_Seas

mnztr wrote:[

The Ford has about 260K hp but AZIpods are super efficient, just 60MW with 3 Azipods can move this behemoth at 25Knots:

https://en.wikipedia.org/wiki/Harmony_of_the_Seas

The ABB marketing department can't be this good : )


The power requied to move the ship and the speed has cubic relationship, menas the 3.5 times bigger engines on the Nimitz can move the ship 53% faster than this crusie ship.


So, twice as big speed require eight times bigger engine.


The azipod has same efficiency advantage, but that is around 5% or maybe less.

Double the turbine size require less weight than the 5% performance gain due to azipods.

Its not as simple as that, the cruise ship is also probably narrower and has a shallower draft. However, azipods put the props in clean water outside of hull effect, and their location is completely independant of the turbines/diesels. I don't really see how this can be "marketing" the ship has done it in sea trials, so it can either do it or not. Also as I said, as Azipods are located subsurface, they are fully displaced and have a reduced requirement of bouyancy from the hull vs systems that are in the engine room. Also they take up very little space. In either case I am sure commercial ship builders are purchasing them for good reasons. If you have a HUGE containership, they use direct drive with massive diesels, no gearbox at all. That is also super efficient .

mnztr wrote:Its not as simple as that, the cruise ship is also probably narrower and has a shallower draft. However, azipods put the props in clean water outside of hull effect, and their location is completely independant of the turbines/diesels. I don't really see how this can be "marketing" the ship has done it in sea trials, so it can either do it or not. Also as I said, as Azipods are located subsurface, they are fully displaced and have a reduced requirement of bouyancy from the hull vs systems that are in the engine room. Also they take up very little space. In either case I am sure commercial ship builders are purchasing them for good reasons. If you have a HUGE containership, they use direct drive with massive diesels, no gearbox at all. That is also super efficient .

1. I have no clue about the shape of the ship, and it is realy doesn't matter - the basic equation given, that govern the speed-power relationship
2. For a small ship it can be, but with bigger ships the pod can't be portrude out of the ship, or the ship navigation capability will be severly restricted
3. You say that the ABB Azipod would float on the water ? the whole cross section of it is metal, copper and iron. And actually how the cost and capability relationships could be affected by this ? If same part of the ship self boyant then it doesn't cost money ?
4. Yes ,because ship operators like the faster docking and the savings on tug fees. But it has no deal with capability of naval ships.

I am still wondering if it would've taken faster to build nuclear powered destroyers than gas turbine powered frigates(both ships with the same weapons systems) given that Russia has a domestic naval nuclear powerplant industry.

Nuclear isn't easy to maintain or operate. They still have soviet nuclear ships rusting at port with no real solution to get ride of them.

Nuclear destroyer will be at the number of 4 max. Even 2 would be extraordinary. Even USSR got only 4 kirovs and was planing 10 Slava along them instead of only kirovs.

Isos wrote:Nuclear isn't easy to maintain or operate. They still have soviet nuclear ships rusting at port with no real solution to get ride of them.

Nuclear destroyer will be at the number of 4 max. Even 2 would be extraordinary. Even USSR got only 4 kirovs and was planing 10 Slava along them instead of only kirovs.

Even during the the hell of the 90s the soviets could maintain at least a dozen nuclear powered subs, and submarine nuclear powerplants are even more complex and difficult to maintain than surface ship ones due to limited space and extreme quieting measures. Thats not mentioning half a dozen massive nuclear icebreakers running nonstop.

Russian maritime nuclear technology is possibly the best of the best in the whole world, and NPPs have advanced massively in terms of reliability, miniaturization and ease of operation, so I don't think the difference between ultra-complex gas turbines and small surface ship NPPs is that big. At least there is no spare part bottleneck with NPPs.

The kirovs were for one, massive(25000t+), and two were rube goldberg machines in terms of propulsion. A 7000-10000 ton destroyer/large frigate with an NPP would be cheaper to maintain and have access to more facilities.

My guess is that they don't want to risk being stuck with huge number of nuclear ships should money ever run out Soviet-style

And yet they're building dozens of arktikas and leader nuclear icebreakers so I dont think the worry of cash running out is there.

PapaDragon wrote:

limb wrote:

My guess is that they don't want to risk being stuck with huge number of nuclear ships should money ever run out Soviet-style

And yet they're building dozens of arktikas  and leader nuclear icebreakers so I dont think the worry of cash running out is there.

You are forgetting one important distinction: warships spend money while icebreakers make money

Naval technology and national prestige makes money too.

Also they do need to build maintenance facilities from scratch for all these nuclear icebreakers, do they not? Whats stopping the russian navy from using these nuclear ship facilities for nuclear powered surface warships? Also if there is a common supply chain for the NPPs of russian nuclear destroyers and icebreakers then maintenance and R&D costs will be cheaper than having to build a gas turbine and marine industry from scratch, not to mention the russian nuclear industry is far less corrupt than the retards at zvezda.

I think investing money in the marine gas turbine market is money well spent... it creates a delay but NPPs for such small ships would also need to be developed from scratch and would equally cause a big delay but also likely add costs to the ships final costs...

They upgraded the propulsion systems on the Gorshkov carrier for India and they have upgraded the propulsion on the Kuznetsov and likely will be improving the propulsion on two upgraded Kirovs and some Slavas too no doubt so it is not like they wont get any experience or need for conventional propulsion systems.

It is not like investing money in a steam catapult system now when it is practically obsolete... investing the same money or perhaps slightly more on EMALS is an investment in brand new and very useful technologies that can be applied in a range of new fields and areas... even if they were to fail there would be progress in other areas anyway, but I rather suspect they will come up with lots of new materials and equipment because of this investment.

GarryB wrote:I think investing money in the marine gas turbine market is money well spent... it creates a delay but NPPs for such small ships would also need to be developed from scratch and would equally cause a big delay but also likely add costs to the ships final costs...

The leader class isn't a small ship, its around 10000 tons. Even super gorshkov equivalents could have NPPs. Why would the NPPs for such ships need to be built from scratch, couldn't reactors from the smaller schuka or yasen submarines be repurposed for surface propulsion? Why not just build leader destroyers in the future with the same reactor as the husky?

Why not just build leader destroyers in the future with the same reactor as the husky?

Unification of designs would make a lot of sense and both improve the investment base... they will have money for sub propulsion development and ship propulsion development, so having a nuclear power plant family that is expandable and standardised would be rather interesting and useful too...

Over time the components will get smaller and cheaper and more powerful and those advances can be applied across the range of platforms using them.

If they can use modular reactors to generate electricity and use this for cruise and gas turbines for sprint that would be idea and cost effective. Most of the advantages of nuclear power at a fraction of the cost.

Picture off RTIM 200 reactor for Arktika icebreaker. This reactor can produce enough electricity for 40,000 HP drive and is impressively small!!!

mnztr wrote:

Picture off RTIM 200 reactor for Arktika icebreaker. This reactor can produce enough electricity for 40,000 HP drive and is impressively small!!!

Maybe they should start converting a lot of the ships that had Ukrainian gas turbine powerplants in to NPP users.

That's just the reactor. Then you need all the rest of the system to use it as an engine and a room where to put it with all the safety needs around it...

Not really possible to put it into old designs not made for nuclear reactor. Unless if you think a nucler incident like Tchernobyl is acceptable.

Having two reactors would be better than one... especially if they could be separated to prevent battle damage to one effecting them both...

It would also mean for cruising purposes one could be shut down and preserved for when more power and speed was needed...

GarryB wrote:Having two reactors would be better than one... especially if they could be separated to prevent battle damage to one effecting them both...

It would also mean for cruising purposes one could be shut down and preserved for when more power and speed was needed...

Much cheaper to have one reactor for cruise and electricity, a few diesel gensets (because you need them anyway) and gas turbines for high speed and redundant power.

Much?

Having multiple different unrelated propulsion systems is good to cover for failure of any one system, but if the ship itself is electric drive then diesels become big and heavy and take up a lot of space for the power they can produce...

Gas Turbines are much smaller and lighter and can generate a lot of power, but also require a rather large volume of fuel...

If you are going to the costs of nuclear power then it makes sense to actually be using it as primary electricity generation source... the backup system could be an enormous bank of batteries that can be used for periods when peak power requirements demand it... and when power requirements drop the Nuclear power generation system can power the ship and also recharge the batteries for when more power is needed... once the batteries are fully charged then they are again ready for when they are next needed...

Fuel cells converting water into hydrogen gas and oxygen gas could be used to store large volumes of hydrogen gas in areas of the ship that are structural but otherwise empty... when needed that hydrogen can be pumped through fuel cells to generate electricity too when needed almost like a giant battery, while the oxygen gas can be used for efficient burning of fuels for cooking and heating etc on the ship rather than stored because of the potential danger or fire risk it would represent.

Batteries are not good in terms off energy density compared to fuel. You would not carry as much fuel as a conventional ship, maybe 1/3 or 1/4. That can also cover helo operations and backup genset power.

It just seems so weird that the russians would cancel all plans to build a nuclear cruiser when they have enough reactors, state of the art off the shelf weapons and sensors, as well as near future free spots in shipyards.