[DrPriyankT]

The INS Vikramaditya which weighs in at around 44k Tons is powered by steam turbines which provide around 180k SHP. The new British Queen Elizabeth class carriers weighing in at around 60k+ Tons will be powered by 4 new Rolls Royce Marine Trent engines which will have around 40k SHP and will have all electric propulsion for energy efficiency and provide enough power for the advanced AESA radars.
The current US navy Nimitz Class behemoths weighing around 100k+ Tons fully loaded have their nuclear reactors providing just enough electrical power to power all the new radars and electronic equipment coming in and so to overcome this the US Navy's new carriers(Gerald R Ford Class) will have a higher electrical load to power their electromagnetic launch systems for planes to take off , their 20 feet diameter AESA radars and weapons of thr future like rail guns and free electron lasers.
Seeing this massive influx of future power hungry weaponry and sensors, I feel that the INS Vikrant will be a bit under powered. Luckily our navy is thinking on having the INS Vishal which will weigh above 60k Tons being propelled by nuclear energy.

[Jeroen]

Originally Posted by DrPriyankT

Td. Luckily our navy is thinking on having the INS Vishal which will weigh above 60k Tons being propelled by nuclear energy.

Not everybody would call that lucky. Nuclear energy is still a controversial topic, whether for onshore or offshore applications.

Jeroen

[Gansan]

Originally Posted by DrPriyankT

The INS Vikramaditya which weighs in at around 44k

Tons is powered by steam turbines which provide around 180k SHP. Luckily our navy is thinking on having the INS Vishal which will weigh above 60k Tons being propelled by nuclear energy.

AFAIK there is no nuclear propulsion as such for ships. The ship will still be propelled by steam turbines. The nuclear reactor merely generates heat to make steam, which in turn drives the turbines.

Similar to nuclear power stations, where also the reactors make steam to turn the turbines which in turn generate electricity.

[DrPriyankT]

Originally Posted by Gansan

AFAIK there is no nuclear propulsion as such for ships. The ship will still be propelled by steam turbines. The nuclear reactor merely generates heat to make steam, which in turn drives the turbines.

Similar to nuclear power stations, where also the reactors make steam to turn the turbines which in turn generate electricity.

I know for a fact that nuclear energy provides just plain heat to provide either steam to propel the turbines to directly drive a ship to propel a ship forwards or it provides kinetic energy to spin turbines to power a generator to produce electricity to drrive a motor to power a ship(called a turboelectric drive and it was pioneered by the french on their nuclear submarine the Rubis).
@Jeoren I for one am a supporter of nuclear power for a nations capital warships as they provide basically unlimited range and flexibility and we should always remember that sea based reactors are very heavily over-engineered to face any evenuality and they have a many a times quadruple to pentaple redundancies built in. Their sheilding is also very heavy(except fot the soviet sheilding on their earlier subs). A testament to this fact is that neither the USS Scorpion and USS Thresher, both US navy nuclear subs which have gone done in the Mediterranean Sea and the Atlantic Ocean respectively, have any radiation leaks from their reactors or associates ancilliaries.

[manas27587]

Happy to see the thread revived.!

Can read a lot of questions from eager enthusiasts!

Since i dont want to quote and make the thread very long, a few short answers to peoples questions.

2S engines are preferred over 4 stroke ones as
1.Power to weight ratio is very high.
2.High torque as already mentioned.
3.Lower speeds as propeller efficiency is highest at lowest speeds.
4. Reduce losses due to gearbox if a 4S is used.
5.Use what we call HFO(Heavy Fuel oil) density as close to 1.

A lot of points already clarified by the Chief engineer on the forum.

As of today,
However we are shifting towards Diesel Electric propulsion.
Secondly Gas based engines already in use.however not successful as the technology is quite new.
Diesel still has to be injected into these gas based engines as the compression temperature inside is not as much as to ignite gas.
Cutting off of units on the main engine is still not recommended because balancing would be disturbed.
Newer technologies introduced use one of the injectors at a time on the unit (Mind you there can be 3-4 injectors on one unit 3 being preferred in the delta formation)
where injectors fire inthe cyclic order at low loads.

I havent worked on the larger engines however.
My largest being a 20000hp Sulzer RTA.
Was a 7 unit 620mm bore size engine.

Have done a FPSO(Floating production storage and Offloading) vessel called the OSX1.
Was a twin screw(2 propellors) drives by 2 wartsilla v12 4S engines producing 6600kw each.
A Controllable Pitch propellor, and 3 Gas turbines of 40MW each.

Specs were awesome however didnt get to work much there as was there only during the installation stage of the vessel in Brazil.

Have been sailing on VLGC's(Very large Gas carriers) always which do not have the big engines.

[Jeroen]

Originally Posted by DrPriyankT

I know for a fact that nuclear energy provides just plain heat to provide either steam to propel the turbines to directly drive a ship to propel a ship forwards or it provides kinetic energy to spin turbines to power a generator to produce electricity to drrive a motor to power a ship(called a turboelectric drive and it was pioneered by the french on their nuclear submarine the Rubis).
@Jeoren I for one am a supporter of nuclear power for a nations capital warships as they provide basically unlimited range and flexibility and we should always remember that sea based reactors are very heavily over-engineered to face any evenuality and they have a many a times quadruple to pentaple redundancies built in. Their sheilding is also very heavy(except fot the soviet sheilding on their earlier subs). A testament to this fact is that neither the USS Scorpion and USS Thresher, both US navy nuclear subs which have gone done in the Mediterranean Sea and the Atlantic Ocean respectively, have any radiation leaks from their reactors or associates ancilliaries.

I think debating whether you call these ships nuclear powered is purely semantics. It is effectively a nuclear reactor, and I for one don't care for them.

By the way, just a little anorak fact: My Chief Engineer rating is valid for all ships, irrespective of size, tonnage and or type of propulsion. So it could be diesel, diesel-electric, traditional steam, or nuclear. So at the naval academy we were taught about nuclear power systems! So I do know a few of the basics. Admittedly not much. The Dutch merchant navy has always been a little short on nuclear powered ships. There have only been a few in the world, apart from ice breakers. None of them particularly successful if I recall.

have a look: http://en.wikipedia.org/wiki/Nuclear_marine_propulsion

The fact that the Thresher and the Scorpion haven't leaked doesn't prove anything. They are just a tomb bomb ticking away if you ask me and at some point in time it is very likely they will start leaking.

Fact of the matter is that we don't know how to dispose of nuclear waste at all. We store it for heaven sake.

A nation with nuclear powered war ships is a nation that builds/has an offensive defense system. There isn't a single argument in the world that I have heard why a nation needs nuclear powered war ships for defensive reasons.

Jeroen

[Gansan]

Originally Posted by Jeroen

There isn't a single argument in the world that I have heard why a nation needs nuclear powered war ships for defensive reasons.

I think they (and similar powered submarines) carry ICBMs = second strike capability dispersed / concealed over a wide area = defense.

[Jeroen]

Originally Posted by Gansan

I think they (and similar powered submarines) carry ICBMs = second strike capability dispersed / concealed over a wide area = defense.

Whether ICBM's are defensive or offensive is in the eye of the beholder. You could also argue, and many have, that if you built a very large defensive system, it becomes offensive by its very nature. What else would you call an arsenal that can destroy the entire world several times over?

Its' definitely a fact that a few nations have been in a "defense" arms race. So again, if you push the other guy to become more defense, he does so because he feels under offensive threat. This is very much the case with these ICBM, be it landbased or marine based.

Think about the START treaty (http://www.state.gov/documents/organization/140035.pdf) which was all about reducing nuclear onshore capability. Read throught the treaty and you will find its about "FURTHER REDUCTION AND
LIMITATION OF STRATEGIC OFFENSIVE ARMS. To me, the purpose of a ICBM doesn't change by providing it with a different launch platform.

Some of this debate is also about the definition of what you would call offensive versus defensive. Some argue that any weapons that targets civilians is always offensive and can not be called defensive.

See: http://books.google.co.in/books?id=e...ensive&f=false

Certainly all of the nuclear hunter submarines the world over are all offensive.

Jeroen

[Jeroen]

Just came across this little table of nuclear information on CNN:


None of these nations would claim to have a nuclear arsenal to go on the offensive. They're all for defense purposes! You can trust us they all claim!

I hope it makes somebody on this planet feel safe, becaue it sure as heck does not make me feel safe!

Jeroen

[CARDEEP]

World's largest ship - The Prelude is launched at a ship factory in South Korea:



http://innovation.uk.msn.com/design/...ip-is-launched

At a whopping 488 metres, it is longer than 4 football fields & there are many other records that this ship has broken, which will be used as a floating liquefied natural gas (FLNG) project.

[14000rpm]

Originally Posted by CARDEEP

At a whopping 488 metres, it is longer than 4 football fields & there are many other records that this ship has broken, which will be used as a floating liquefied natural gas (FLNG) project.

There is a lot more such vessels coming which will head to North Sea where Deep sea explorations are taking an upswing. This also comes with totally new challenges in the way the hulls are designed to handle rough sea while holding full oil production and storage facilities. these are called FPSO's.
I was in a dinner meeting with the CEO of one of the more famous engine suppliers to this industry who was also telling me about the next boom in oil coming from the Brazil and African regions.

sidenote : if you are an engineer (mechanical/Electrical/marine) having some involvement in O&G area and wish to migrate to Norway, now is your time. They have a shortage of 10000 engineers.

[Thad E Ginathom]

Watch the video on the BBC here.

What a stunning piece of ship handling by the tugs. Quite amazing. Pity we can't see it in real time.

[alpha1]

Originally Posted by DrPriyankT

we should always remember that sea based reactors are very heavily over-engineered to face any evenuality and they have a many a times quadruple to pentaple redundancies built in. Their sheilding is also very heavy(except fot the soviet sheilding on their earlier subs). A testament to this fact is that neither the USS Scorpion and USS Thresher, both US navy nuclear subs which have gone done in the Mediterranean Sea and the Atlantic Ocean respectively, have any radiation leaks from their reactors or associates ancilliaries.

Is there any study done to assess the change in health of crew due to radiation?
The reason why I ask this is because in traditional industrial setting (in India), I have seen many industry claim that their process is safe and blah blah (basically nice and safe sounding words). However, if you see - many of the plant operators who have worked for 20-30 years DO develop some or the other typical issue in such hazardous chemical/dust industries. No one ever does any such study. Ideally the basis of this study should then dictate the human safety & health measures in the next upcoming project.

[CARDEEP]

Originally Posted by 14000rpm

There is a lot more such vessels coming which will head to North Sea where Deep sea explorations are taking an upswing. This also comes with totally new challenges in the way the hulls are designed to handle rough sea while holding full oil production and storage facilities. these are called FPSO's.
I was in a dinner meeting with the CEO of one of the more famous engine suppliers to this industry who was also telling me about the next boom in oil coming from the Brazil and African regions.

sidenote : if you are an engineer (mechanical/Electrical/marine) having some involvement in O&G area and wish to migrate to Norway, now is your time. They have a shortage of 10000 engineers.

with the part in bold. In fact, it is mentioned in the report I attached in my post.

Disclaimer: I had little interest in these BHP giants, until when I read last few pages of the thread. I am hooked, & will try to bring out the news, but, no tech details as I am no (marine) engineer... rather a poor accountant.

[14000rpm]

Originally Posted by CARDEEP

with the part in bold. In fact, it is mentioned in the report I attached in my post.

oh. Did not see the report. My clientele are in this domain therefore I am deeply involved in this domain and know a bit of the market dynamics.