Russian AIP submarine technology

...if they are using luquid oxygen there for AIP fuell cell, they could use cooling for high temperature superconductors for propeller engine - significant reduction in mass and weight + 99% efficient from 1 rpm - 600 rpm.

RMF... you talk about storing hydrogen on board a sub as problematic and then you talk about storing oxygen without mentioning it is vastly more problematic and outright dangerous.

`well hydrogen is to be avoided as stored - risky ,hard to contain , boils off, large volume ,and mass of tanks.
oxygen benefits from high density , easier storage temperatures , low boil off technologies (developed for space) less then 1% per month , you can use deep cooled slush form to buy some time ,etc...

Pure hydrogen is totally inert... it is only hazardous if you get the mix of hydrogen and oxygen correct to get fire. You need very very specific conditions to get an explosion... surround the hydrogen tank with nitrogen and it should be totally safe.

Pure oxygen will burn at the smallest spark and you wont be able to put it out. It turns anything that will burn at normal air pressure and normal temperatures into an explosive under pressure in an oxygen rich environment.

Incredibly dangerous.

Regarding the process of extracting the needed chemicals from Diesel... first of all it is genius because every port able to support a submarine will already have the infrastructure to supply diesel... while a hydrogen fuel cell AIP requires pure hydrogen which means all new infrastructure for all of your ports... and foreign ports you want your subs to operate from.

Note I am not saying you are wrong about storing hydrogen, but storing oxygen is vastly more complicated and lead to use of things like HTP for slightly safer storage.

usualy for supeconductors liquid nitrogen is used, and its used anyway as surface layer for liqud oxygen storage and tank flushing.
hydrogen is vastly more complicated to store and contain.
if sub is using cryogenics anyway it could store some extra nitrogen for submarine propeller motor. that motor would be very small. liquid nytrogen is -200c liquid and oxygen is -220c.
http://nextbigfuture.com/2009/01/365-megawatt-superconducting-motor.html

But the point in terms of danger, Nitrogen is inert and apart from being under pressure and very cold is no real danger to the crew. Hydrogen is not much worse in the sense that it needs oxygen to burn and underwater there is not much available oxygen... especially if stored outside the internal hull and surrounded by water.

Oxygen on the other hand is always dangerous and the smallest spark can start a fire that very few things on earth or in space or in water could stop.

A fire needs fuel and oxygen and heat... water normally is excellent for putting out something like paper on fire because it stops oxygen getting to the flame, it cools down the hot material and can turn fuel materials like wood or paper into non fuel materials that wont burn unless extremely hot.

A LOX fire combines fuel and oxygen in one in such a vigorous fire that even water wont stop it. LOX will burn underwater or in a vacuum... that is why LOX is a component of rocket fuel... liquid hydrogen practically explodes in LOX.

point is oxygen is a must for any AIP so i really dont know what your babble is about....

My problem is that if you think Hydrogen is a problem to store and handle then LOX is a PITA.

The best compromise is to store it as HTP and "release" it when needed.

yeah HTP in submarines and torpedoes was always a great idea -not

Much safer that LOX.

As long as HTP is kept away from catalysts it can pretty much be treated like water.

LOX is always dangerous.

`yes yes ,much safer , thats why all the navies in the world have given up on it....
htp stores many times less oxygen per volume as liquid oxygen.

htp stores many times less oxygen per volume as liquid oxygen.

True, but HTP stores energy in two forms... let it flow through a catalyst and a lot of heat and O2 is released... the heat can be used to drive a turbine and generate electricity directly and the O2 can be used in any number of ways to generate electricity...

LOX stores O2 is a volatile form that could explode at any time.

`yes yes ,much safer , thats why all the navies in the world have given up on it....

No they have not.

And what navies of the world carry LOX in tanks on submarines?

As I have been saying LOX is much less safe that liquid hydrogen or HTP.

anyway nice derail of topic , i wont argue anymore ,just to spite other users your inventing stuff and twisting words ,your lack of knowledge is astounding...instead of admitting you dont have a clue.
typical know-it-all-guy.... htp is safer and better , look at submarine record who used it, even in torpedoes its not used
and O2 from liquid oxygen is less safe then super hot steam and O2 from peroxide, sure

Yeah, make it personal.

O2 is the most flammable material there is even a static spark can cause combustion, and in a pure O2 environment there is no such thing as a fire... material that burns in normal conditions in a pure O2 environment explode.

And you think hydrogen peroxide is MORE dangerous to store.

Keep it away from a catalyst and it is just like water.

Cryogenic O2 from LOX is just as dangerous to human tissue as super hot steam from hydrogen peroxide.

And your claim that no navies use HTP is rubbish because not all navies are western navies.

yes and gasoline is just like water ,as long as there is no flames its perfectly safe , - thats how riculous your claim is.... go around world navies and tell them to reintroduce hydrogen peroxide
liquid oxygen is used commercially in every place stored in steel dewart bottles and tanks, and it is used in submarines outside pressure hull( any boiloff is less then 5% per month!!! is vented into ocean) , not to mention hot O2 from htp would damage fuell cell unlike cool oxygen , you have no clue and still sinking furhter ....
https://www.google.rs/?gws_rd=ssl#q=liquid+oxygen+tank+types

[qutoe]yes and gasoline is just like water ,as long as there is no flames its perfectly safe[/quote]

Yes... actually it is like water... Petrol is a fuel but to actually burn it needs oxygen... without it it is harmless.

Hydrogen is the same... without large amounts of oxygen Hydrogen is either a very high pressure gas or super cooled gas, which means not as safe as water but not as volatile as LOX which is both super cold and also an extreme fire hazard.

- thats how riculous your claim is.... go around world navies and tell them to reintroduce hydrogen peroxide

The Russian navy never withdrew its HTP powered torpedoes.

Might come as a shock, but the chemicals that fuel SLBMs are rather more volatile and more dangerous and also more toxic than Hydrogen Peroxide.

liquid oxygen is used commercially in every place stored in steel dewart bottles and tanks, and it is used in submarines outside pressure hull( any boiloff is less then 5% per month!!! is vented into ocean) , not to mention hot O2 from htp would damage fuell cell unlike cool oxygen , you have no clue and still sinking furhter ....

Speaking of no clue, stored in the fuel tank of a torpedo, HTP is no more dangerous than a Li ion battery... which can also explode if mishandled BTW.

The HTP in a torpedo is inert when kept away from a catalyst and when the HTP is doing its job of powering the torpedo who cares if it damages a fuel cell? Hot drives a turbine that propels the torpedo through the water... Hot is good.

Quite interesting topic, I mean the question of the most effective non nuclear , air independent power source : )

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

Hydrogen + oxigen energy density : 13.43 Mj/kg
H2Oh (hydrogen peroxyde) energy density - as monopropelant : 2.7 Mj/kg
Lithium ion energy density is 0.5 Mj/kg, lead acid is 0.14 Mj/kg.


all data down here aprox , from the top of my head.
The efficiency of the hydrogen fueal cell can be 60-90% , the efficiency of a swassplate engine around 20-30% for H2O2.

The problematic is the hydrogen storage, the density of the liquid H2 is 70 kg/cubic meter, and the boiling point is under the freezing point of the liquid oxigen, so it needs good heat insulation on the separator plate as well.

The hydrogen - air will detonate int the 5-95% range , so it is one of the most dangerous gases.


Carbohydrogen based fuel cell has very bad efficiency, it is way better if an internal combustion engine burn the fuel.

I have to menation that you can buy liquid oxigen by truckload, but no company on the earth will deliver to anyone liquid hydrogen.
All industrial hydrogen generated on site, by partialy oxidating the natural gas.

The whole point in developing hydrogen peroxide is to make the storage of oxygen stable.

Introduce a catalyst and you get heat, free oxygen and water. The heat means you get that water in steam form.

No one will deliver liquid hydrogen because it would be far to expensive to create a cylinder that could handle material at near absolute zero and keep it at that temperature.

Compressed hydrogen is a very reactive gas but the gas itself only explodes under pressure and simply burns invisibly when exposed to oxygen and heat.

Liquid hydrogen is a cryogenic rocket fuel but requires liquid oxygen to be so.

GarryB wrote:The whole point in developing hydrogen peroxide is to make the storage of oxygen stable.

Introduce a catalyst and you get heat, free oxygen and water. The heat means you get that water in steam form.

No one will deliver liquid hydrogen because it would be far to expensive to create a cylinder that could handle material at near absolute zero and keep it at that temperature.

Compressed hydrogen is a very reactive gas but the gas itself only explodes under pressure and simply burns invisibly when exposed to oxygen and heat.

Liquid hydrogen is a cryogenic rocket fuel but requires liquid oxygen to be so.

Let tnik a bit.

The H2O2 can be used as oxigen source as well, but the problem is the CO2.

The hyrdogen burn to water, means it is quite easy to condensate and eject it on a submarine, but anything else burn as Co2+H2O, means you need energy and complicated compressor to eject the exhaust.

The H2O2 as monopropelan in best case has two times higher energy density than the Lion battery, but I think in real life application it is on par with the batery pack.

Means that the peroxide and lion battery submarine has the same submerged time for the same fueal/battery mass, but the h2o2 submarine will be noisy, due to the piston engine.

So, the peroxyde is not an ideal fuel for quiet submarines.


The hydrogen+oxigen fuel cell doesn't has moving parts, it generating electricity quietly, but it need either extreme pressure to store the hydrogen, or cryogen canisters.

So, at the end of the day the lion battery + diesel is the most practical solution, everything else will has higher cost.

ofcourse russia is using another fuels for new torpedoes and whitdrawing htp ones like all others, kursk mulitibilion and 180 lives tragedy is enough.  not to mention htp is disaster in taking combat damage , while liquid oxygen in water just turns to gas and dissapates because its surrounded by -water.

tanks would be outside of pressure hull , in amur 1650 project  tank was to be in the middle of submarine so it was abandoned project , liquid oxygen technology is fully commercial and mature , pound for pound you get much more energy then htp and less volume. fuell cell converts more efficient then any combustion motor , so when you need gaseous oxygen you jsut run it trough intercooler using ocean water to heat it up to -50C and then run cool oxygen trough fuel cell which they use , fuell cells of that type dont like heating and hot oxygen you get from htp , that also eliminates cooling pumps and equipment..

Rmf wrote:ofcourse russia is using another fuels for new torpedoes and whitdrawing htp ones like all others, kursk mulitibilion and 180 lives tragedy is enough.  not to mention htp is disaster in taking combat damage , while liquid oxygen in water just turns to gas and dissapates because its surrounded by -water.

tanks would be outside of pressure hull , in amur 1650 project  tank was to be in the middle of submarine so it was abandoned project , liquid oxygen technology is fully commercial and mature , pound for pound you get much more energy then htp and less volume. fuell cell converts more efficient then any combustion motor , so when you need gaseous oxygen you jsut run it trough intercooler using ocean water to heat it up to -50C and then run cool oxygen trough fuel cell which they use , fuell cells of that type dont like heating and hot oxygen you get from htp , that also eliminates cooling pumps and equipment..

Fuel cell works only with hydrogen, if you concerned with efficiency.
With any carbohydrogen the efficiency will drop to 10%ish.
So, the problem is not the oxygen, that is easy, but the hydrogen, that is the tricky part.

The H2O2 can be used as oxigen source as well, but the problem is the CO2.

What CO2?

CO2 is generated when fossil fuels are burned, but if you burn something with no carbon in it then you don't get CO2 or CO.

Fuels are burned to generate pressure or heat to drive a turbine... H2O2 creates the pressure and heat on its own with the gas produced being O2.

Fora torpedo design you could have a fuel tank with H2O2 and a fuel tank with H in it... the H2O2 can be pumped over a catalyst to generate heat and O2 and then pure hydrogen added and burned in the super hot steam... burning H in O2 and you get H2O... more water... so super hot steam will come out the back of the torpedo... the turbine driven by the super hot steam can be directly connected to the propeller to drive the torpedo.

Unlike a battery there is no chance of it going flat if left over time.

So, at the end of the day the lion battery + diesel is the most practical solution, everything else will has higher cost.

The Russians reportedly have developed a fuel cell that extracts hydrogen directly from diesel fuel.

This has the enormous advantage that diesel is already carried on the submarine and every port on the planet already had the capacity and infrastructure to transport and deliver diesel to pier side. Not so with hydrogen.

kursk mulitibilion and 180 lives tragedy is enough.

Wow... another 62 die? That stuff must really be lethal... or perhaps it is you that are not totally sure of what you are talking about?

My understanding was that 118 men died on the Kursk?

not to mention htp is disaster in taking combat damage , while liquid oxygen in water just turns to gas and dissapates because its surrounded by -water.

Really... REALLY!!!

So HTP releasing some O2 in a sub is a disaster but much more concentrated O2 is just perfectly safe and just dissolves into thin air...

Combat damage will likely be an explosion or a fire... both of which will be immensely magnified by the presence of LOX.

tanks would be outside of pressure hull , in amur 1650 project tank was to be in the middle of submarine so it was abandoned project , liquid oxygen technology is fully commercial and mature , pound for pound you get much more energy then htp and less volume. fuell cell converts more efficient then any combustion motor , so when you need gaseous oxygen you jsut run it trough intercooler using ocean water to heat it up to -50C and then run cool oxygen trough fuel cell which they use , fuell cells of that type dont like heating and hot oxygen you get from htp , that also eliminates cooling pumps and equipment..

Fuel cells run on hydrogen, not oxygen and why not use the ocean water as an intercooler for HTP?

Or perhaps do what the Russians are actually doing and create a fuel cell that uses diesel fuel... :rolleyes:

[quote="GarryB"]

So lets repeat it again.

If the H2O2 used on its own, as monopropelants,then the energy density of it will be the same as the lion batteries. but the peroxide need noisy turbine or reciprocating engine, the lion ned silent electrical motor.

So, using H2O2 as monopropelant not a great idea, since the second world war.

As oxigen source either you use diesel, then there is the problem of CO2, or hydrogen, but if you have hydrogen then it is trivial and cheap to store liquid oxigen as well.


The chemistry is not the submariners friend in this case.

If you use diesel,with air then the energydensity 35Mj/kg, diesel efficiency is 40% ,s you have 14Mj effecive energy on the shaft of the engine.

If you bring your oxigen and hydrogen liquid, then the energy density is 20 Mj/kg, efficiency of the fuel cell is 80%, means 16 Mj/kg efficiency on the shaft, roughly the same as the diesel+air.


So, if your bring the oxigen as H2O2 then that will cut into half the energy density , means 8 Mj/kg.You still need criogen hydrogen.

Now, if you move to the next level, and bring diesel + H2O2 with you, but you don't want to oxidate the carbon then the final energy content will be something like 5,5 Mj/kg, with fuel cell the shaf energy will be 4 Mj/kg.

The lion battery has energy density of 0,5 Mj/kg.


See?

If you consider the mass of all H2O2 container, chemical reactor, partial diesel oxidator, heat exchanger and fuel cell then the effective submerged range will be between 2-6 compared to the lion battery pack, but the final cost will be several times higher.And of course you still has between 500-1000 tonns of H2O2 on board.

And the H2O2 submarine will be way more noisy than the lion battery one, of course.


So, it makes more sense to use very quiet ,high efficiency internal combustion engine to recharge the batteries, than to use comlicated chemical processes on board .
And the H2O2 will be more noisy than the lion submarine of course.

Singular_trafo wrote:

So, it makes more sense to use very quiet ,high efficiency internal combustion engine to recharge the batteries,  than to use comlicated chemical processes on board .
And the H2O2 will be more noisy than the lion submarine  of course.

so why hose damn sub designers did not follow this simple idea? maybe because there´s no internal combustion engine as quiet as current AIP?

BTW what would you do with exhaust engine? not to mention fule and heat.

GunshipDemocracy wrote:

Singular_trafo wrote:

So, it makes more sense to use very quiet ,high efficiency internal combustion engine to recharge the batteries,  than to use comlicated chemical processes on board .
And the H2O2 will be more noisy than the lion submarine  of course.

so why hose damn sub designers did not follow this simple idea? maybe because there´s no internal combustion engine as quiet as current AIP?

BTW what would you do with exhaust engine? not to mention fule and heat.

: )

I can't see any announcement of H2O2 + reduction agent propelled subarines, so my logic hold the water : ).

Singular_trafo wrote:

GunshipDemocracy wrote:

Singular_trafo wrote:

So, it makes more sense to use very quiet ,high efficiency internal combustion engine to recharge the batteries,  than to use comlicated chemical processes on board .
And the H2O2 will be more noisy than the lion submarine  of course.

so why hose damn sub designers did not follow this simple idea? maybe because there´s no internal combustion engine as quiet as current AIP?

BTW what would you do with exhaust engine? not to mention fule and heat.

: )

I can't see any announcement of H2O2 + reduction agent propelled subarines, so my logic hold the water : ).

Yup this water is called perhyrol sometimes

BTW we talk not about diluted solutions for suicide blondes Real perhydrol is explosive and toxic for humans. Like Me-163 used this as monopropellent. No good for pilots in case of problems.


It would be dangerous to use concentrated on subs. Not to mention costs and noise.


Talking about subs:

" In the 1940s and 1950s, the Hellmuth Walter KG-conceived turbine used hydrogen peroxide for use in submarines while submerged; it was found to be too noisy and require too much maintenance compared to diesel-electric power systems. "

could aditional rtg generator in 100kw range, using some advanced technologies thermionic ,stirling ,photovoltaic and thermovoltaic ,be used on conventional submarine. it would wok non-stop thus charging cells while submarine is still in position.