Ideal battleship design

[RF]

If a Battleship is required then I must turn to the argument of a very big ship that can withstand heavy punishment and can be able to outgun her enemies.
I don´t like the H-Class, but not for her size or any ideological adversion but because they are not ideal. The H-Class with 8 x 16" guns is not a good option because the Iowas are more or less their match and, in every way, Yamatos outgun them. And if we are talking about a 120,000 ton 20" gunned H-Class then we better have a warp drive and photon torpedoes. Nope. Let´s have some BB that can be build...
My ideal ship is more or less a combination of Yamato+Iowa+Bismarck.
Let´s see:

1. 12 x 16" guns (4 triple turrets)
2. Armour: an upgrade of Bismarck´s but with more depth and lenght in their belt armour, stronger deck and turret armour.
3. No underwater torpedo tubes.
4. No diesel, nah, let´s have boilers with turbines
5. Four shafts in an arragement very similar to CVN Enterprise or Nimitz Class. She must be able to have some steering with her propellers.
6. Heavy, but very heavy, AA defense. Every space in her deck and superestructure MUST be filled with proper AA bateries. (let´s say, some sort of naval 88 mm?)
7. One funnel.
8. Catapults for... what? A couple of naval modified ME 109... That´s cool!
9. Very high and strong superestructure and redundant bridges.
10. It must be painted with Baltic Camo just because of the looks.

Displacement: around 65 to 70,000 tons.
Lenght: 885 ft. (270 meters)
Speed: 31 knots (that means 200,000 hp)

Well that´s it. Destroy it please... :negative:

I would propose destruction by submarines, at night, on the surface, firing torpedoes on one flank.

The biggest is not necessarily the best, and in any case, the experience before WW1 is that the winner in these stakes is the one with the greatest ship-building capacity.

[RF]

I almost forgot. Limpet mines. Attack the ships bottom, warp the hull shape, just as with Tirpitz.

[RF]

Is really a choice of using diesels in such a ship? How was the supposed diesel powerplant for Scharnhorst composed?

This is never really explained, as the engines as far as I am aware, were never developed.

[Karl Heidenreich]

In a old thread there were mention to Schanhorst boiler problems. When I asked about them the answer was that the boilers were installed as an emergency option because the original design call for the use of diesels.
But they never explained to me which were the problems with Schanhorst boilers.

[RF]

In a old thread there were mention to Schanhorst boiler problems. When I asked about them the answer was that the boilers were installed as an emergency option because the original design call for the use of diesels.
But they never explained to me which were the problems with Schanhorst boilers.

I think the problems with the boilers were similar to those in the German destroyers in that the rapid ''superheating'' start up didn't work and caused pipes to burst. I gather the difficulty was that the boilers were rushed into production to get the ship built without proper testing and pre-planning.

[Dave Saxton]

Diesel is in many ways better than steam turbines, as long as the power per shaft requirements can be meant. Diesel is the easiest and cheapest refined fossel fuel to produce in large quanities. It's also one of the most economical fuel sources when used. It's obvious why a nation like Germany would be attracted to it to power their navy.

Steam turbine systems were probably not ideal for ships used as Atlantic raiders. Super heat steam systems like to be run hard or not at all. Idling around to conserve fuel, but mostly lit up, so high power can be obtained in short order, is asking for problems. In super heat systems, turned down, you will get a high liquid fraction in the vapor stream, and that eats up turbine blades. This problem will be compounded by chloride erosion.

It was chloride erosion that was the big problem. Chloride erosion is intensified by increased heat and pressure. The Germans had this problem fairly well solved through the use of 347 stainless steel by 1941, but how does the chloride get into the system to begin with?

When a superheat system is run at or above designed parameters, the SR flow or steam rate needs to be increased. The capacity of the SR volume is reduced in normal operation to reduce efficiency losses due to entropy. This reduction of volume, reduces the possible number of energy states. However, there must be a heat transfer out of the system, as the system volume is reduced, or if it becomes more extended. In high performance systems, additional but cooler water is introduced into the system, and excees heat exchanged out of the system, with the vapor passing over the liquid state feed water, in direct contact. Indirect contact does not work quickly enough. Direct contact pre-heats the feed water, as it condenses the vapor. It's more efficient, but ultimately less durable.

With high performance super heat systems, it's possible to exceed the normal max output of the system by a considerable amount. Internal combustion diesel engines of the time simply could not produce the same amount of power, even with considerably more weight expended. Super heat steam was much more power to weight efficient. If turbo supercharging of the diesel engines was possible, as it is now, then diesel power could deliver the required power, within the space and weight limitations.

Turbocharged diesels would be a more ideal power plant, than steam in many cases.

[RF]

erosion.

It was chloride erosion that was the big problem. Chloride erosion is intensified by increased heat and pressure. The Germans had this problem fairly well solved through the use of 347 stainless steel by 1941, but how does the chloride get into the system to begin with?

I believe that most German destroyers suffered major corrosion problems right up to 1945, which is one of several reasons why they wanted diesel engined destroyers. The engines were designed but Germany was losing the war and the engines not produced because they were competing with other production demands.

[RF]

Diesel is in many ways better than steam turbines, as long as the power per shaft requirements can be meant. Diesel is the easiest and cheapest refined fossel fuel to produce in large quanities. It's also one of the most economical fuel sources when used. It's obvious why a nation like Germany would be attracted to it to power their navy.

Steam turbine systems were probably not ideal for ships used as Atlantic raiders.

This was certainly the experience of the Hipper classe cruisers and of Widder, Orion and Thor.

Internal combustion diesel engines of the time simply could not produce the same amount of power, even with considerably more weight expended. Super heat steam was much more power to weight efficient. If turbo supercharging of the diesel engines was possible, as it is now, then diesel power could deliver the required power, within the space and weight limitations.

Turbocharged diesels would be a more ideal power plant, than steam in many cases.

.

The Germans had already developed tubo-charged diesel engines for their Schnellboote, but these were only small engines, up to 2,500 SHP. It is not clear why these were not developed further, for use in U-boote as well as surface ships.

[Bgile]

Diesels apparently still aren't able to produce the necessary power for a warship or they would be in use today. The only use has been to provide auxiliary cruising engines in some designs and I think even those have been discarded.

An obvious example is the US Navy, were most surface combatants are being built with gas turbine engines.

I really think diesels only work really well when you can run them at exactly the same speed, day after day. Combat ships can't do that.

[Karl Heidenreich]

Dave Saxton:

When a superheat system is run at or above designed parameters, the SR flow or steam rate needs to be increased. The capacity of the SR volume is reduced in normal operation to reduce efficiency losses due to entropy. This reduction of volume, reduces the possible number of energy states. However, there must be a heat transfer out of the system, as the system volume is reduced, or if it becomes more extended. In high performance systems, additional but cooler water is introduced into the system, and excees heat exchanged out of the system, with the vapor passing over the liquid state feed water, in direct contact. Indirect contact does not work quickly enough. Direct contact pre-heats the feed water, as it condenses the vapor. It's more efficient, but ultimately less durable.

That problem with the chloride erosion was a headache to the engineers in Hood also. Weeks ago I posted in this forum about it.

[RF]

Diesels apparently still aren't able to produce the necessary power for a warship or they would be in use today. The only use has been to provide auxiliary cruising engines in some designs and I think even those have been discarded.

An obvious example is the US Navy, were most surface combatants are being built with gas turbine engines.

I really think diesels only work really well when you can run them at exactly the same speed, day after day. Combat ships can't do that.

The US Navy also had the advantage of not having any of the fuel supply constraints that the Germans had, so fuel economy never went into US calculations, so no incentive to use diesels on surface ships.
I believe the US did construct larger diesel engines for their Pacific War subs though.

The German ships on raider duty generally did operate with less speed variations for longer periods than in home waters, so diesels for long range cruising were more appropriate in that situation, which was unique to the Germans.

[Bgile]

The US Navy also had the advantage of not having any of the fuel supply constraints that the Germans had, so fuel economy never went into US calculations, so no incentive to use diesels on surface ships.
I believe the US did construct larger diesel engines for their Pacific War subs though.

The German ships on raider duty generally did operate with less speed variations for longer periods than in home waters, so diesels for long range cruising were more appropriate in that situation, which was unique to the Germans.

To say that fuel economy never went int US calculations is absurd. The requirement was to operate over a much larger ocean than the Germans made it essential. US ships probabably had longer cruising range ship for ship than any other navy. BUT, they couldn't use diesel power because of the reasons I already gave; primarily maximum SHP being too low.

Submarines are completely different. They were very small ships and didn't use large engines. They were also slower, at about 20 kts max speed on the diesels. They had 3 or 4 of them. They used diesel electric drive, which solves the speed flexibility problem with constant speed diesels, but can't generate the shp of a turbine plant.

[Bgile]

I want to also point out that the US Navy did choose diesel power for "Destroyer Escorts", which the British called Corvettes. These little ships were used to escort slower ships. They could do 24 kts and were faster than submarines, but no fast enough to work with combatant task forces. The diesels were of course efficient and gave them good range.

[Tiornu]

You're thinking of frigates. The corvettes were an extension of a whaler design.

[Karl Heidenreich]

The Buckley Class ships were escort destroyers and were not a whaler design.