Indian nuclear submarines

[singh100ful]

So should we expect something as silent as the akula class that we have, or will the Russians help us make something close to Yasen class? Akulas stealth profile is already a little behind the curve compared to the latest subs.

It needs to be seen as of now which class of submarine is russia willing to provide but IN does not want it to be of AKULA class.

 

[Kshithij]

Because that's the way Th cycle works in Th based reactor.

India has less quantity of U235 so obviously for India it will be costly. And since India is working on it's own reactors so looks like they are training the crew on this AHWR with LEU + Th

It could be vast it's all presumptions. No one would actually know what they are upto.

India has 2-2.5lakh ton of Uranium. Now, calculate 0.71% of it. We get 1400-1750tons of U235 (100% purity). This is about 14lakh to 17.5 lakh kilograms of U235. This may be comparatively small, but not too small. Only fools use U233.

Is there vacuum between the two inner hulls?, is there is an onboard vaccum pump to regulate vacuum?

There is no vaccuum. The two are connected at various joints, but there will be enough spacing to not let the whole noise come out. Most of the noise dies down while transmission. However, some noise is inevitable as nuclear reactor continuously pumps water in and out to produce power and also to keep itself cool. Even IR signatures can be obtained. This is a common problem for nuclear submarine

 

[piKacHHu]

here are 2 types of reactor - PWR (PHWR) and LWR.

PWR reactor can work in both in Raw uranium as well as enriched uranium - from LEU to HEU. India prefers PWR (or PHWR) reactors as they are efficient plutonium producers and also produce energy as efficiently as LWR reactors. One can simply feed the natural uranium without any enrichment and obtain energy as well as plutonium in this reactor. PWR reactors can also be refueled without shutting them down. The only reason to shut down PWR is for maintenance. These reactors are also compact in nature. But, due to their pressurised way of working, they can't be expanded to 1GW or above easily and will need special precautions to contain pressure

LWR uses only enriched uranium and can't work in natural uranium. These reactors can work in LEU as well as HEU and produces reactor grade plutonium, not weapons grade plutonium. The plutonium is produced more slowly and have higher content of Pu240 which is not desirable. These reactors also need to be stopped while refueling.

Overall - PWR reactor is the best reactor for weapons purpose. LWR reactor is scalable and hence more cheaper for energy production. PWR reactor is also compact making it best suited for submarines, carriers etc.

Now, about usage of LEU or HEU depends on the needs. HEU will mean longer time for refueling while LEU will need short time for refueling. Enriching Uranium is a technology which India, Pakistan, North Korea and pretty much all nuclear countries have obtained. Even Iran was enriching Uranium. I don't understand why some people are shouting that costs will be higher. In case of submarines, the reactors are tightly enclosed and refueling is a big deal. So, the best way to save costs is to get HEU which will last much longer and generate more power for a smaller size.

Enrichment is an easy process. It is the opening of submarine to refuel that increases cost. So, best way to save cost is to use HEU which lasts in excess of 10 years in almost all cases. For example, a 40% enriched Uranium has over 55 times more uranium 235 than an unenriched raw uranium of same weight

India also has 2lakh tons of Natural Uranum. Setting aside 1000-2000 tons for a few dozen nuclear submarines is not a big deal

Let's correct some facts that you have posted:
1. PWR & LWR are not different types of nuclear reactors. LWRs i.e. Light Water Reactor are the reactors that use light water or ordinary water as cooling medium. It is further categorize as PWR i.e Pressurized Water Reactor and BWR i.e. Boiling Water Reactor.
PHWRs i.e Pressurized Heavy Water Reactors, on the other hand, uses Heavy water as cooling reactor and it comes into a different category. Currently, most of the power generating nuclear reactors that India has is of PHWR type.

2. PWR or BWRs can't run on raw or natural uranium. They need enriched uranium as fuel which is the reason why India doesn't have many of them running. Instead, we use PHWRs which uses natural uranium as fuel. Though, we are scaling up our enrichment technology to produce PWR grade fuel.

3. PWR needs to be shut-down for refueling. It's the PHWR that can be operated while refueling is taking place.

India prefers PWR (or PHWR) reactors as they are efficient plutonium producers and also produce energy as efficiently as LWR reactors. One can simply feed the natural uranium without any enrichment and obtain energy as well as plutonium in this reactor.

4. Pure Gibberish. What you are talking about is the Fast Breeder Reactors which is entirely different concept and not related to reactors used in nuclear submarines.

But, due to their pressurised way of working, they can't be expanded to 1GW or above easily and will need special precautions to contain pressure

5. Again wrong fact. VVER-1200 & Westinghouse reactors are commercially proving reactors having power rating more than 1.2 GW-electrical. It's not the operating pressure of the reactors that limits it's up-scaling. It's combination of requirements, plant economics, thermodynamics, & material limitations.

6. Enrichment is Not An Easy Process Dude !! Pakistan obtained it through IPR theft so as the North Korea. We have to develop it from the scratch with no help available.

7. Designing a nuclear reactor compact enough to fit into a section of submarine while taking all the necessary safety to contain radioactivity is a big task. The USA was pioneer in designing early nuclear submarines (USS Nautilus et al. ) in early 50s but as we all know what kind of financial & technological resources were at their disposal. Despite all failures & setbacks, We have succeeded with Arihant and we would repeat our success with bigger and more capable U-Boats in future.

PWR Basics
https://en.wikipedia.org/wiki/Pressurized_water_reactor

USS Nautilus
https://en.wikipedia.org/wiki/USS_Nautilus_(SSN-571)

 

[Kshithij]

Let's correct some facts that you have posted:
1. PWR & LWR are not different types of nuclear reactors. LWRs i.e. Light Water Reactor are the reactors that use light water or ordinary water as cooling medium. It is further categorize as PWR i.e Pressurized Water Reactor and BWR i.e. Boiling Water Reactor.
PHWRs i.e Pressurized Heavy Water Reactors, on the other hand, uses Heavy water as cooling reactor and it comes into a different category. Currently, most of the power generating nuclear reactors that India has is of PHWR type.

2. PWR or BWRs can't run on raw or natural uranium. They need enriched uranium as fuel which is the reason why India doesn't have many of them running. Instead, we use PHWRs which uses natural uranium as fuel. Though, we are scaling up our enrichment technology to produce PWR grade fuel.

3. PWR needs to be shut-down for refueling. It's the PHWR that can be operated while refueling is taking place.

4. Pure Gibberish. What you are talking about is the Fast Breeder Reactors which is entirely different concept and not related to reactors used in nuclear submarines.


5. Again wrong fact. VVER-1200 & Westinghouse reactors are commercially proving reactors having power rating more than 1.2 GW-electrical. It's not the operating pressure of the reactors that limits it's up-scaling. It's combination of requirements, plant economics, thermodynamics, & material limitations.

6. Enrichment is Not An Easy Process Dude !! Pakistan obtained it through IPR theft so as the North Korea. We have to develop it from the scratch with no help available.

7. Designing a nuclear reactor compact enough to fit into a section of submarine while taking all the necessary safety to contain radioactivity is a big task. The USA was pioneer in designing early nuclear submarines (USS Nautilus et al. ) in early 50s but as we all know what kind of financial & technological resources were at their disposal. Despite all failures & setbacks, We have succeeded with Arihant and we would repeat our success with bigger and more capable U-Boats in future.

PWR Basics
https://en.wikipedia.org/wiki/Pressurized_water_reactor

USS Nautilus
https://en.wikipedia.org/wiki/USS_Nautilus_(SSN-571)

PHWR reactors produces lot if plutonium. Breeder reactor also produces plutonium. But, Breeder reactor requires initial plutonium which it uses to breed more. It is irrelevant to what I am saying

Again, about enrichment, enrichment is not hard. India already has enrichment ability as seen in fuel for Arihant. Also, once technology is obtained, it can be run at the expense of some coal power and manpower. No need of more expense

 

[Screambowl]

India has 2-2.5lakh ton of Uranium. Now, calculate 0.71% of it. We get 1400-1750tons of U235 (100% purity). This is about 14lakh to 17.5 lakh kilograms of U235. This may be comparatively small, but not too small. Only fools use U233.

India is signatory to US on use of anything uranium due to NSG thing and US nuclear deal. There fore complete independence on both resource and enrichment is the I'm of all countries.

Pokhran 2 had W grade U233.
This is highly fissile due to the presence of u232 in it this is the reason it is used in weapon. And you can produce a lot of it directly from Th (natural) also for nuclear submarine. For lesser mass it can produce more energy as compared to HEU 235.

But since its a very potent tech it has disadvantage that is U232 decays into beta particles and there fore it's easy to be detected. There fore an extra work or absorbing material is most probably needed to absorb beta emission.

The whole discussion becomes invalid because no one knows what they are using or what kind of reactor they have.

 

[piKacHHu]

Pokhran 2 had W grade U233.
This is highly fissile due to the presence of u232 in it this is the reason it is used in weapon. And you can produce a lot of it directly from Th (natural) also for nuclear submarine. For lesser mass it can produce more energy as compared to HEU 235.

But since its a very potent tech it has disadvantage that is U232 decays into beta particles and there fore it's easy to be detected. There fore an extra work or absorbing material is most probably needed to absorb beta emission.

For your Reference:
"Uranium-232 (232,92U, 140, 232U, U-232) is an isotope of uranium. It has a half-life of 68.9 years and is a side product in the thorium cycle. It has been cited as an obstacle to nuclear proliferation using 233U as the fissile material, because the intense gamma radiation emitted by 208Tl (a daughter of 232U, produced relatively quickly) makes the 233U contaminated with it more difficult to handle." Source: Wiki

So, U-232 doesn't decay into beta particle, rather it is a long lived product of thorium decay chain undergoing Beta decay. Beta particles are not a big issue to deal with but it's high energy gamma radiation which requires extensive shielding for doing any handling operation. This is perhaps the most challenging aspect for utilizing Thorium fuel in any nuclear reactor.

Propulsion reactors of this age are essentially PWRs as they are compact and more efficient than any other of class of reactors. Depending up on the requirements, they could be designed in a way which would require no refueling in their entire service life.

Those who wants to know more about nuclear propulsion reactor can read a wonderful research paper by Ragheb which is available in public domain.
Link:
http://mragheb.com/NPRE 402 ME 405 Nuclear Power Engineering/Nuclear Marine Propulsion.pdf

 

[kurup]

Some good information about French Naval Reactors ..... https://fas.org/wp-content/uploads/2016/12/Frances-Choice-for-Naval-Nuclear-Propulsion.pdf

Another excellent article ..... HEU v/s LEU for Naval reactors ,

http://www.nti.org/media/pdfs/Replacing_HEU_in_Naval_Reactors_Report_FINAL.pdf?_=1458832580

 

[Screambowl]

So, U-232 doesn't decay into beta particle, rather it is a long lived product of thorium decay chain undergoing Beta decay.

Beta decay emitting beta ray / beta particle also know as energetic electron or positron and also produce gama radiation. But it's the gama which is problematic. This is reason why U232 give out fluorescent colour in dark.

 

[ramdas hegde]

http://gentleseas.blogspot.co.id/2015/10/submarine-propulsion-test-reactor-needs.html?m=1
Indian Submarine Propulsion Reactor Needs - Arihant, Aridhaman & Chakra II
Photo of "S-1" land based prototype reactor at Kalpakkam for India's Advanced Technology Vessel (ATV) (Arihant) Program. S-1 went critical on November 11, 2003, was declared operational on September 22, 2006 and photographed (above) in early August 2009. Kalpakkam is an Indian nuclear enclave 45 km south of Chennai, on India's lower east coast. Kalpakkam is shorthand for the longer, more formal, name of the nuclear enclave which is the Indira Gandhi Centre for Atomic Research (IGCAR) (Photo courtesy
The Hindu ).
---
[Update as at March 27, 2017] The Submarine Matters article below was originally published in October 2015 - which explains why the comments below it are of October 2015. The article is suggested reading before I publish an overt update on India's nuclear submarine program on March 30 or 31, 2017.
Please connect with Submarine Matters US and France in Talks with India to Assist India's Nuclear Submarine Program, September 29, 2015.
INDIA'S INDIGENOUS REACTOR PROGRAM FOR SUBMARINE
The land based prototype reactor at Kalpakkam was designated "S-1" in India's Advanced Technology Vessel (ATV) (Arihant) Program,
"S-2" - was INS Arihant itself with its 83 MW 1st or 2nd generation reactor
"S-3" is INS Aridhaman the first true SSBN (yet to be launched) which will have a more powerful 2nd or 3rd generation reactor.
The Indian indigenous nuclear submarine program, that produced the Arihant, continues under some secrecy. Secrecy is not total because Kalpakkam and its parent organisation, the Bhabha Atomic Research Centre (BARC), need to demonstrate to politicians and the public that the large amounts of taxpayers money is spent wisely with progress made in the nuclear projects.
• Work on the Indian nuclear sub program dates from the 1970's and was referred to as the Advanced Technology Vessel (ATV) Project .
• The prototype nuclear propulsion plant at Kalpakkam (photo) was developed under the program "Plutonium Recycling Project" or "PRP" under direction of BARC or Bhabha Atomic Research Center (BARC). Kalpakkam nuclear enclave is 45 km south of Chennai on the lower east coast of India.
• The Kalpakkam-Arihant prototype plant went critical on November 11, 2003 and after further development was declared operational on September 22, 2006. It was only shown to the press once, in early August 2009, about one week after the July 26, 2009 launch of the Arihant itself. Apparently only one photo (above) was cleared for distribution.
• Most sources list the prototype and the Arihant reactors as being rated at 82.5 MW. There are around 13 fuel assemblies with each assembly having 348 fuel pins.
Major components of Arihant's reactor were made by Indian companies, including:
- the reactor vessel, made of special grade steel by Heavy Engineering Corporation, Ranchi.
- steam generator by Bharat Heavy Electricals Limited (BHEL) and
- Pressure valves were made by Audco India, Chennai.
ARIHANT's REACTOR PERFORMANCE
There is a great deal of difference between a nuclear propulsion reactor in a submarine and a land-based atomic power station to produce electricity. While a land-based atomic power plant gets backup from other power stations on the electrical grid, a submarine nuclear propulsion reactor only has some weak diesel engines for emergency backup. A propulsion reactor has to be miniaturised to fit into the confined space of a submarine and be lightweight but strong enough to endure the shock due to moderately powerful underwater explosions. The reactor must also withstand the pitch and roll of a submarine. The reactor must also be capable of rapidly accelerating and decelerating the submarine - unlike a land-based power plant which ramps up gradually.
The Arihant's 83 MW reactor went critical after many sea trials. Extrapolating from known data on Russian submarines and their reactors - the Akula class has a 190 MW reactor but turbines that are rated at just 32MW. Going by the roughly 20 percent power rule here, the turbines on the Arihant are likely to be around 15 MW, or about 20,000 horsepower. Rating them at higher than that doesn't seem to make much sense, and the figures placing them at 47,000 hp (on
wiki right sidebar ) seems ludicrous - that sort of power would propel the Arihant's estimated 6,000 tons (surfaced) (perhaps 7,000 tons submerged) bulk past 37 knots (like a high speed SSN). A lower power rating and a speed in the SSBN range of 24 knots seems far more likely. A ballistic missile submarine isn't meant to sprint across the ocean s - it's meant to be a ghost, running silent and deep, popping up to deliver its apocalyptic cargo when the time calls.
Arihant, with its 83 MW reactor, must be considered an interm and experimental test bed. The 83 MW reactor is not powerful enough for the second of class INS Aridhaman SSBN . Aridhaman, to carry a larger missile load, may weigh around 8,000 tons (surfaced). So a more powerful reactor, approaching Chakra II's 190 MW reactor, may be India's objective.
INDIA INTERESTED IN CHAKRA II'S 190 MW REACTOR
A major reason for India funding Chakra II ( ex Nerpa Akula's) completion and 10 year lease is Indian interest in developing a reactor with something approaching 190 MW. It is logical to assume that India has a prototype 190 MW reactor at Kalpakkam with Russian advisers for technology transfer. The Akula SSNs, like Chakra II, use the OK-650 reactor rated at 190 MW. It uses a low end 20%-45% HEU reactor. The OK-650 may have been first used 1980 and is still being placed on new Russian submarines - such as 2 on the Borei SSBN in 2009. The OK-650 and other 190 MW Russian submarine reactors are made by the OKBM Afrikantov company.
Of nuclear submarine powers India may still have reactors less advanced than China's but ahead of Brazil. The most advanced remains the US. USS Nautilus was launched in January 1954 and its reactor went critical in December 1954, under two years after the land based prototype went critical. The US provided the UK with its best reactors and helped the UK build copies. France may have received direct US-UK assistance or they tacitly permitted "espionage" by France.
INDIA INTERESTED IN FRENCH AND US REACTOR ASSISTANCE
As at September 2015 India appears to be encouraging Russia, France and the US to compete in providing nuclear submarine assistance to India. Russia is an overt provider of assistance while France and US may claim that are not actually assisting in Indian submarine reactor development.
Biswajit Pattanaik advised in Comments [ Oct 2, 2015 8:42PM ] India may want a reactor similar to the K15, 150 MW that France has in the Barracuda SSN. Years ago a retired Indian Navy Admiral said the Navy asked BARC to develop a 190 MW with HEU for possible use for the 2nd Vikrant class aircraft carrier and future SSBNs and SSNs that will appear after 2025 time frame. Biswajit understands India is seeking French assistance to increase the life of the Indian reactor from the current 5-8 years to around 10-15 years. India may also be talking to French reactor builder AREVA about converting the K15 from LEU to a new HEU type reactor.
Ultimately India would be very interested in developing a reactor approaching the capabilities of the US Virginia class's ninth generation S9G reactor which uses higher HEU of 90+ % and lasts the lifetime of a submarine (33 years).

 

[ramdas hegde]

old but very good ...,..........................................................

 

[ramdas hegde]

very good article .read comments some solid info there.
http://gentleseas.blogspot.co.id/2017/08/ins-aridhamans-probably-symbolic-launch.html?m=1

 

[ramdas hegde]

almost identical to Arihant/Aridhaman class ,Ethan allan class(USN).
they also look almost identical.
https://en.wikipedia.org/wiki/Ethan_Allen-class_submarine

 

[Willy2]

As U233 is risky.

What kind of risk against others ? higher radiation ?

 

[Screambowl]

What kind of risk against others ? higher radiation ?

To explain one more time briefly.

In thorium cycle when you produce U233 from Th232, small amount of U232 is also produced, which undergoes beta (minus) decay and produces TI208 which then emits gama radiation.
The gama radiation is highly penetrating and strongest of all. This is general physics.
This is why it makes it very difficult to work with.
https://en.wikipedia.org/wiki/Uranium-232

 

[Babloo Singh]

Indian Navy Submarine Arm Gets Presidential Colors !!
Just wondering if President's Visit has something more in agenda...... (Aridhaman)

 

[WolfPack86]

Indian nuclear submarines.
https://twitter.com/SJha1618?ref_src=twsrc^google|twcamp^serp|twgr^author

 

[WolfPack86]

Indian govt must go for additional 6 nuclear attack submarine.

 

[sayareakd]

Congrats to all, two Indian made nuclear power and nuclear weapons carrying in water.
Best part all things done quietly.

 

[aditya10r]

Indian nuclear submarines.
https://twitter.com/SJha1618?ref_src=twsrc^google|twcamp^serp|twgr^author

Will gormint order more subs?????

I guess no.

We need at least 45 subs(ssk+SSN) to dominate IOR.

_________________________________________

 

[Kshithij]

India is signatory to US on use of anything uranium due to NSG thing and US nuclear deal. There fore complete independence on both resource and enrichment is the I'm of all countries.

Pokhran 2 had W grade U233.
This is highly fissile due to the presence of u232 in it this is the reason it is used in weapon. And you can produce a lot of it directly from Th (natural) also for nuclear submarine. For lesser mass it can produce more energy as compared to HEU 235.

But since its a very potent tech it has disadvantage that is U232 decays into beta particles and there fore it's easy to be detected. There fore an extra work or absorbing material is most probably needed to absorb beta emission.

The whole discussion becomes invalid because no one knows what they are using or what kind of reactor they have.

What kind of risk against others ? higher radiation ?

U233 is definitely fissile and can be used in bombs as well as nuclear reactors. The problem with it is its half life of 68 years which means uranium stored will continuously get depleted quickly. And it is more riskier due to higher chance of auto trigger.

U233 is not even 1% lighter than U235. This difference in weight is insignificant compared to the disadvantage U233 offers. A nuke made of U233 will not detonate after 10 years as 15% would have been depleted due to short half life. No one likes to use such material.

India is not reliant of USA or NSG to extract its Uranium indigenously. Indian Uranium is free from any restrictions and can be used as per Indian will

Will gormint order more subs?????

I guess no.

We need at least 45 subs(ssk+SSN) to dominate IOR.

_________________________________________

45 is not enough. We not only need high quality submarine but also large numbers of them. In war attrition rate is something one must consider. To be able to quickly make up losses, low cost submarines are also needed