[Ranb]

A problem that hydrogen causes at high pressures is that it is forced into the crystal lattice of steel, where it reacts with the carbon, makes methane, and weakens the steel.

This phenomenon is a problem in the manufacture of ammonia, and it might have been there that it was first discovered, I don't know. The hydrogen and nitrogen are pumped into a cylinder to high pressure. "Low alloy" steels must be used. That's usually stainless steel.

Modern US Naval reactors do not use stainless steel where exposed to hydrogen and high temperatures. Nickel based alloys are the most commonly used now. Hydrgen concentration can also be limited in the primary to prevent damage.

Ranb

[Ranb]

I wonder about the psychology of a crew of men being underwater for a year.

A Polaris missile is supposed to launch from under water. Compressed air is how they say it's done. It does seem doubtful to me that such a thing could be done. I wonder why they have never used one?

It is rare that a sub crew is underwater for more than 90 days. Food, spare parts and chemicals required for operation of the plant are much more limiting than the fuel.

Compressed air used to be the way a ballistic missile was launched from the submerged submarine to the surface. The method used today is a mixture of propellant and steam. This method does not require the use of the ship's air banks.

Ranb

[Ranb]

I do wonder whether the 1954 film might have been a promo device to make underwater ships look a lot easier and safer than they maybe were. Anyway, Verne's mythical 'Nautilus' had a lot of electrical stuff, including cooking, which at the time must have been serious science fiction.

_______________________
His idea of a sub was not to have large water-filled tanks, to make the thing able to sink; "What would you think if you had to fill your car half-full of water before you drove it off?" he said to me. Instead you have a heavy cylinder - maybe reinforced concrete. The thing would have 'wings' and the equivalent of ailerons and a tail, but, since water is so much denser, these would be more stub-like. It would be piloted underwater like a plane. He worked out an escape procedure, because, like a shark as popularly imagined, it would have to keep moving to avoid sinking.

In 1954 subs (nuclear and diesel) typically used electricity to operate many things. While hydraulics and high pressure air were and are still used to operate planes and rudders, electricity is the easiest and safest for most of the rest of the gear on a sub.

The weight of the ship's hull (cylinder) is limited in part to the amount of weight permitted by the design of the ship. Ballast tanks are either empty (on the surface) or full (submerged). Much smaller trim tanks are used to adjust for changes in the sub’s mass as it operates and to adjust for buoyancy as required. The crew can use a nose up or noise down trim, or be negatively or positively buoyant depending on the needs of the mission. The current method of submarine trim was worked out prior to WWI.

Ranb

[Ranb]

One of cactusneedles' comments was that submarines could be recharged electrically by underwater cable; and after all there are undersea cables crossing the globe.

Why use an extension cord when you can used on board fuel instead? Same reason a car on gasoline has a much higher range than one on batteries only. While nuclear powered subs are capable of connecting to a shore facility for their power needs when the reactor is shutdown in port, these power connections are far too inadequte for powering the sub while it is on its missions.

Ranb

[Ranb]

Maybe they could be recharged by induction? Or have some arm that sticks out like on an electric train, to contact a railing?

What you said about underground cables; I hadn't thought of that. There's lots of them down there. And a sub crew member wouldn't know what was going on. He was just know the sub was stopped for some reason, which he didn't need to know, and so wouldn't be told. Or told a cover story.

There are no electrical connections capable of handling large amounts of current outside of the hull or just inside the hull for the purposes of inductive current on any US nuclear powered subs. I am very familiar with the designs of 637, 688 and 726 class subs. It is common for a sub to transit at high speed nearly coast to coast while preparing for a mission. In other words, no time to stop for a battery charge. While there may be frequent trips near the surface during a high speed transit for messages and other housekeeping duties, the sub rarely ever stops unless something else requires it. It is easy to tell when a sub stops in the water. The sound and motions it makes change significantly when stopped, going slow or going fast.

Ranb

[FirstClassSkeptic]

It is rare that a sub crew is underwater for more than 90 days. Food, spare parts and chemicals required for operation of the plant are much more limiting than the fuel.

Ranb

Then why the need for an endless supply of nuclear energy? This is starting to sound like the nuclear air craft carriers, which must have fuel replenished each day.

Ranb, I am a skeptic, so you can't persuade me by telling me about everything you've seen and done.

Have you ever seen a nuclear submarine launch a nuclear missile, and destroy a city?

[Ranb]

I have not seen a sub launch a missile and destroy a city; there is no credible evidence that this has ever happened.

The supply of power is not endless on a sub or any other nuclear powered vessel; they need to be refueled at some point and near the end of the core's life there are limitations based on core xenon.

Using a longer lasting fuel reduces the need to take fossil fuels onboard which allows room for other consumables. It is easier to make the food and parts last longer than diesel fuel. Nuclear power also allows for long term high speed submerged transits; something that is not possible with any other type of submarine propulsion.

Carriers only need to have fuel brought on board each day when they are doing flight operations. At other times their use of nuclear propulsion allows them to sprint to any location on the globe within days or weeks.

What evidence would it take to convince you that nuclear propulsion exists on subs and carriers? What evidence do you have to support your claims?

Ranb

[rerevisionist]

'Ranb' wrote ---
Why use an extension cord when you can used on board fuel instead? Same reason a car on gasoline has a much higher range than one on batteries only. While nuclear powered subs are capable of connecting to a shore facility for their power needs when the reactor is shutdown in port, these power connections are far too inadequte for powering the sub while it is on its missions.

[1] You're assuming there is onboard fuel available. If the nuclear system works, then that's OK. If, as seems likely, it doesn't work, you have to recharge, either by going to a port or some other recharging point, or using some other method, typically diesel. But of course this needs air. AS FCS points out, if the thing has to come to shore frequently anyway, what's the evidence for or need for nuclear power?

[2] You make, maybe unconsciously, a very telling point when you talk about when the reactor is shutdown in port. Why should it be shutdown; and, if it is, how can you be sure it ever worked?

[3] Definitive evidence would be, presumably, that the total non-nuclear power used by a 'nuclear sub' is nowhere enough to power it. Can you prove that?

[4.1]Have you ever checked the schematics or drawings of a nuclear sub, and checked the sub actually matches?
[4.2] Have you ever maintained or helped maintain or supervised the maintenance of the nuclear propulsion part(s) of a submarine? Or for that matter built, of helped build one?
[4.3] Have you followed the process, or taken part in decommissioning or scrapping nuclear submarines?
You could have interesting information!

[Ranb]

Why is it likely that the reactor does not work? I am able to detect the radiation levels increasing as the reactor starts up and as the power levels change. There is no source for this radiation other than the fuel, the decay products and nitrogen-16 in the coolant.

I am most familiar with nuclear submarines. They are not allowed to operate the reactor in port outside of entering and leaving unless they have special permission. This has to do in part with the limited emergency cooling equipment available in the limited space on board the ship. A sub will operate the reactor for in port testing only after certain repair operations.

Another reason to shut down the reactor is that is conserves the fuel load and allows for reduced manning on board. The crew gets a break as operating a ship that is shutdown does not require as much attention. I can tell by temperature levels, vibration and radiation levels that the reactor and steam plant is operating or shutdown.

I have checked drawings and plans, they match. It takes more than 10K horse power to push a 4000 ton ship through the water at greater than 20 knots. The steam plant is less than 30% efficient due to the simple rugged design required of the reactor and steam plant. Most of the energy is wasted to the sea and a significant portion of the rest is used for generating electrical power as much is needed to cool the reactor and power other loads devoted to operating a warship.

All nuclear powered ships require extensive maintenance and repairs that normally take place in port, a sub is unable to perform most of these repairs unless in port or in drydock. A nuke sub can travel for months at greater than 20 knots uninterupted while the best AIP subs can only creep around at a bout 5 knots for less than a month. This give the nuke subs a great tactical advantage. This is obvious to anyone who really studies them. It appears that you have not.

I was previously qualified to operate and maintain the nuclear propulsion plant on a submarine. Currently I work in a shipyard where I help maintain and also recycle the old plants/subs. My NEC in the USN was 3366. I am currently a physical science technician.

I answered your questions, care to reciprocate? What evidence do you have to support your claims?

Ranb

[rerevisionist]

You haven't answered the questions. Anyone can make up such statements; the point is the proof. The evidence appears to be consistent with these vessels not having to be nuclear powered, and the steps taken consistent with concealing this; you don't seem to realise submarines existed decades before the claimed nuclear power, or that just general technological progress could explain what ncreases seem to have occurred.

Ther's also a serious problem at the root of all nuclear power, which is that it needs a chain reaction; however according to the usual model of radioactive fission, this must inevitably get out of control; any exponential increase such as is supposed to happen would blow the thing up.

[Ranb]

I did answer your questions, what don't you like about them? Are you going to continue to evade answering my questions of you?

I know subs existed long before the first nuclear powered sub in 1954. The USA bought their first submersible in 1901, and they were used in the American revolutionary and civil wars also.

Which technical progress do you think was not possible?

What is the problem with containing a nuclear reaction? In a nuclear ship's reactor, the core is composed of uranium oxide clad with zirconium. Neutron absorbing control rods keep it highly subcritical (shutdown) until they are slowly pulled out to bring it critical (self sustaining neutron population). When the reactor is at power and hot, it is temperature that drives power up and down according to steam flow from the plant.

This stable condition is achieved by designing the reactor with a negative co-efficient of reactivity. Simply put, when temperature goes up, power goes down. This is because when the moderator heats up, is it less dense and more neutrons from fission leak out of the core instead of causing fission. When temperature goes down, more neutrons stay in the core and cause fission, therefore making power go up.

Another way power is controlled is that the core cannot stay critical without delayed neutrons, those that appear from decay of fission products. This slows down power transients and makes the reactor much easier to control. It is not magic or a fraud, it is knowledge and engineering.

Ranb

[rerevisionist]

[1] You're assuming there is onboard fuel available. If the nuclear system works, then that's OK. If, as seems likely, it doesn't work, you have to recharge, either by going to a port or some other recharging point, or using some other method, typically diesel. But of course this needs air. AS FCS points out, if the thing has to come to shore frequently anyway, what's the evidence for or need for nuclear power?

[2] You make, maybe unconsciously, a very telling point when you talk about when the reactor is shutdown in port. Why should it be shutdown; and, if it is, how can you be sure it ever worked? ** To put it another way, if they're so dangerous in port, why are they less dangerous at sea?

[3] Definitive evidence would be, presumably, that the total non-nuclear power used by a 'nuclear sub' is nowhere enough to power it. Can you prove that?

[4.1]Have you ever checked the schematics or drawings of a nuclear sub, and checked the sub actually matches?
[4.2] Have you ever maintained or helped maintain or supervised the maintenance of the nuclear propulsion part(s) of a submarine? Or for that matter built, of helped build one?
[4.3] Have you followed the process, or taken part in decommissioning or scrapping nuclear submarines?
You could have interesting information!

You haven't given any detailed facts or figures on performance. You haven't stated whether you've observed or maintained or decommissioned nuclear engines. You haven't addressed the issue of remote recharging of batteries. You haven't addressed the issue of how it can be possible to prevent a catastrophic fission. (Or - if you did - why it is that nuclear bombs wouldn't get hot, presumably to melting point, since for such huge amounts of energy this would be easily achieved). All you do is quote something you've read.