Fuel consumption Bismarck

Propulsion systems, machinery, turbines, boilers, propellers, fuel consumption, etc.
dunmunro
Senior Member
Posts: 3118
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: Fuel consumption Bismarck

Postby dunmunro » Thu Jan 19, 2012 3:58 am

alecsandros wrote:
dunmunro wrote: For example Iowa would not be able to allow her displacement to fall below ~55000 tons due to the need to maintain liquid in the outboard layers of her TDS.

What % load of fuel oil and ammunition did you have in mind to arive at this displacement ? Remember only Friedman gives IOwa's total maximum late-war displacement at ~ 59.000tons, with 8000 ton fuel and 2000 ton ammo on board... Other sources mentino full loads at ~ 57.000
tons.


The average displacement was 56500 tons, in 1943-44:

http://www.ibiblio.org/hyperwar/USN/ref ... el-BB.html

According to G&D the optimum battle displacement for Iowa was 55424 tons but this figure would increase as more AA armament was fitted.

alecsandros
Senior Member
Posts: 3992
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania
Contact:

Re: Fuel consumption Bismarck

Postby alecsandros » Thu Jan 19, 2012 6:26 am

dunmunro wrote:
According to G&D the optimum battle displacement for Iowa was 55424 tons but this figure would increase as more AA armament was fitted.

My point exactly. Richelieu and VV should also be compared at battle displacement in this case.

Why no words on the Vanguard ? It may have been the fastest European battleship ?

delcyros
Member
Posts: 213
Joined: Mon Feb 07, 2011 9:26 pm

Re: Fuel consumption Bismarck

Postby delcyros » Thu Jan 19, 2012 4:14 pm

As a general point of interest. I prefer to use real data and not fix fudged attempts to account for differences in displacement. That beeing said, I see no reason to assume what You said is correct with the limited data at hand to draw my conclusions.

And it's even more fuzzy when comparing it to data points coming from Richelieu or Vittorio VEnetto with 25-30% loadings and maximum output (and in the case of Ricehlieu, even forced output). Iowa with 25% load would displace ~ 49000t, which, at 240000shp may theoreticaly exceed 34-35kts, clearly faster than any competitor.

Sorry, but that´s utter nonsense. The power family curves simply don´t behave like a cube fit in the 30kts region of the IOWA´s.

IN the same time, Richelieu/Littorio/Tirpitz with 75% load (45.000/45.000/49.000 tons respectively) would be stuck in the 30-31kts area at best, while Iowa with 75% load would displace ~ 55.000t and possibly exceed 32kts.


Again, where do You take this speculation from? Sustaining these claims only degrades Your credibility, Alexandros.
During trials in june, RICHELIEU sustained 32.0 kts (avg.) in 3.5 steaming hours at a displacement of 43,800t (that is 50% load!) with 155,000SHP (design speed) and reached 32.69kts at 179,000SHP forced (=119% design power) acc. to Jordan and Dumas. That figure represents the highest speed ever recorded under known conditions for a battleship. At 25% more load (that are 1,200t only!) -You seem to be confident that RICHELIEU´s top speed drops to 30-31 kts but that isn´t correct. The model tests predicted a top speed of 32.1kts at 75% load (=45,000t) and 33.2kts at ~20% load (41,000t) with 120% power (=180,000 SHP and well below the point where cavitation set´s in). In real life, RICHELIEU was unnoticably faster than the model predicts at some speeds and slower at others -within the margins of experimentational error if You dare to calibrate the model predicts with the trial data curves.

It´s slightly faster than what NEW JERSEY could hope to achieve in 1943. Altough the trials were carried out at 1,600t larger displacement (85% load seems reasonable), she would have been hard pressed to achieve 31.2 to 31.3 kts at design power (=212,000SHP) instead of the 31.5 to 31.6kts of RICHELIEU (MMF model from 75% load model dataset) and when forcing and may have achieved 32 kts but hardly exceed this figure as long as cavitation sets in.

The Iowa's had 20% overload capacity (so up to 255.000hp) AND New Jersey was 85% loaded (12.000 load / 14.000 tons maximum load). So, again, the IOwa class is demonstrated to be the fastest BBs ever built...

Unfortunately, the max. output of 255,000SHP isn´t going to help beyond 240,000SHP becaue the extra power is rapidly wasted in creating steam by the cause of cavitation. It requires five shafted propulsion to exploit power in excess of 240,000SHP with period technology (or in excess of 180,000SHP in case of the twins, BISMARCK & TIRPITZ with their three shafted propulsion). Very cold or very dense water would delay cavitation a bit, so it´s probably better if the props sit as deep as possible but then again, deep loads create the problem that more power is needed to overcome wetted drag.
RICHELIEU is free of these constraints and could have forced the engines to 130 or 140% without fearing to engage in cavitation, provided that the machinery was capable to deliver these high overload powers, which I don´t know.
Demonstratedly, RICHELIEU has the claim to be the fastest battleship. It left a trial record at speeds in the 32.0 to 33.0kts range. The IOWA´s never did. In two cases, under controlled conditions, their machinery developed problems so that max. power couldn´t be attained both times.
What we are left with are predictions- or, alternatively expressed, extrapolations of the known data, which usually end at 29 to 30kts. Perhaps IOWA was indeed faster, in 1985 with specially treated props and modern, plastic underwaterpaint than was RICHELIEU in 1940, but the difference appears to be negliable.

With regard to battle displacement, please stay in an objective perspective. The USN ships had different requirements with regard to the desried battle load displacement of their fighting ships owing to very different set´s of requirements. The french and italian ships were not long legged and perfectly suited for action in the Mediterranean Sea, where lower loads would be tolerated owing to the short distances involved here. You realistically could see a RICHELIEU at 43,000t operating.
USN ships required different theatres and higher ranges, too. You hardly ever see an IOWA below 56,000ts displacement as long as minima in protection against underwater damage are to be acknowledged. If the fuel is used up, it get´s replaced by seawater to fit the 56,000ts.

but again, that´s only my opinion, feel free to have a different one.

alecsandros
Senior Member
Posts: 3992
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania
Contact:

Re: Fuel consumption Bismarck

Postby alecsandros » Thu Jan 19, 2012 6:07 pm

Dear Delycros,
I see you put a lot of work into your reply; I hope I'll explain myself better here than in the above posts.

Firstly, I also prefer real data in opposition to predictions. One such real data presents Vittorio Venetto "never exceeding 28 - 29kts in the war years". [Bagnasco]
Vittorio Venetto achieved 31.42kts@134616hp@238rpm. Displacement: 41.134 tons! (434 tons above standard displacement!)
Taking a 40.700-ton nominal battleship at 41.134tons for speed trials is complete non-sense, since the full-load displacement was 45.000t. This corresponds to ~ 10% load.

Secondly, a just comparison should take into consideration the capabilities of various ships operating in the same constraints. Of course Richelieu and VV had lesser loads than Iowa, because of the geography of the Mediteranean. But that doesn't represent an advantage "per se" over the Iowa class. Let's take the Iowa class and put it in the Med. And then loads of 51-52000 ton would become the new average... Or take the Richelieu into the Pacific, and watch it at 46.000tons, and in tropical/ecuatorial waters...

Thirdly, if you are to be very critical over a particular test, or a particular extrapolation, you should be that critical with all the other tests/extrapolations,
I've seen pages of rebutals of Iowa's maximum speed. I do not agree with several of the issues raised, but this is not the point I'm trying to adress now.
The point is : Why don't I see rebutals of Richelieu's 32.6kts ? Or of Vittorio Venetto's 31.4kts ? (see above ?)
G&D mention "tests on 13June 1940. 43.000 tons, 179.000hp, 32.6kts". As far as I know, the Richelieu was not completed at this time. The ship was only completed after her New York Naval Yard refit, and the new maximum speed is listed in G&D at 31.6kts. Moreover, thorough speed tests performed in 1951-1952 showed the ship could not reach speed of 30kts [i]in tropical waters, 29kts being the maximum.[/i] (G&D Allied battleships bottom of the page table on pg 141)

Fourthly, you should be as sure as you can be that the tests you are comparing[/i]have been done using similar methodologies.

Fiflthly You should take into consideration the particulars of the sea/air on the particular day/days of the test/s. Differences of more than 1kts are known to appear between tests done in shallow/deep water, or between tropical and temperate waters, etc.

Thus, the results obtained by the European battleships in operational conditions(except maybe Vanguard) are not convincing faced with teh results obtained by various ships of the Iowa class...

alecsandros
Senior Member
Posts: 3992
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania
Contact:

Re: Fuel consumption Bismarck

Postby alecsandros » Thu Jan 19, 2012 6:26 pm

Edit:
What's wrong with Friedman's figure from "US Battleships"?

New Jersey Dec 1943 , standardization trials: 31,9kts @ 221.000hp @ 56928 tons

This shows 85% loaded New Jersey as being faster than the 10% loaded VV, and then the refited Richelieu...

User avatar
Dave Saxton
Supporter
Posts: 2890
Joined: Sat Nov 27, 2004 9:02 pm
Location: Rocky Mountains USA

Re: Fuel consumption Bismarck

Postby Dave Saxton » Thu Jan 19, 2012 8:41 pm

delcyros wrote:Image


and

These are the MMF models for IOWA (from her trial in 1985 with modern and smoother underwaterpaint) and USS NEW JERSEY as of 1943. ....USS IOWA was a bit faster at est. 31.9 kts at 212000SHP in 1985 for the reasons outlined above. USS NEW JERSEY would have been unable in 1943 to attain 31.0 kts at 56,000 t displacement with 212000 SHP an couldn´t be expected to exceed 31.8kts despite forcing the engines. The max. speed these vessels could attain lies right in between 31.0 and 32.0 kts, but closer to the latter.


Thank's this is real good information.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.

delcyros
Member
Posts: 213
Joined: Mon Feb 07, 2011 9:26 pm

Re: Fuel consumption Bismarck

Postby delcyros » Fri Jan 20, 2012 12:14 pm

Edit:
What's wrong with Friedman's figure from "US Battleships"?

New Jersey Dec 1943 , standardization trials: 31,9kts @ 221.000hp @ 56928 tons

This shows 85% loaded New Jersey as being faster than the 10% loaded VV, and then the refited Richelieu...


This isn´t from the standartization trials (which were conducted in oct). This data comes from the fuel economy trials conducted in dec.
Next, the displacement was measured before the run, and not averaged from measurements before and after the run
and most notably, the top speed attained in these trials was not 31.9 kts but 31.0 kts at 221,000SHP (BuShip source):

Image


As far as the LITTORIO class goes, I have not attempted to do anything, mostly because of the lack of data. I would stay away from statements unless a series of data, not only including a top speed figure, emerges.
That beeing said, I am aware that the typical italian habit of executing ultra-light load trials is well documented in case of some cruisers at least, so it wouldn´t surprise me much to see it also appearing in their battleships.

But that doesn't represent an advantage "per se" over the Iowa class. Let's take the Iowa class and put it in the Med. And then loads of 51-52000 ton would become the new average... Or take the Richelieu into the Pacific, and watch it at 46.000tons, and in tropical/ecuatorial waters...

Point taken. The difference as far as I see it -and I may be wrong- is that IOWA would require more deep draught for questions of stability and underwater protection, something not much affecting the reatively low loadable RICHELIEU and LITTORIO.

if you are to be very critical over a particular test, or a particular extrapolation, you should be that critical with all the other tests/extrapolations,
I've seen pages of rebutals of Iowa's maximum speed. I do not agree with several of the issues raised, but this is not the point I'm trying to adress now.

I am not very critical. Only as far as anectdotes go, having seen so much unbased claims to reject these sources completely.
I am basing my opinion on primary sources. For NEW JERSEY in 1943 the results from standartization trials (conducted in between a low of 56,200 and a max of 56,800ts displacement) the results are aviable now:
Image
As You can see, the max. output attained was 163,400 SHP, representing a speed of 29.3kts.

A boiler casualty prevented full power trials in the standartization trials. The same thing which besett the trials in 1943 happened with USS IOWA in 1985, preventing her from making full power trial runs because of a boier breakdown. In both cases the data from the fuel economy trials, conducted at approximately equal load, were added to the trial data from the standartization trials to extrapolate a theoretical max. speed. I used both sets of data, fuel ecoenomy and standartization trials from NEW JERSEY to make an MMF model, which is in excellent agreement not only with the data but also with the conclusions of BuShip as regard to her top speed.

The point is : Why don't I see rebutals of Richelieu's 32.6kts ? Or of Vittorio Venetto's 31.4kts ? (see above ?)

You may feel uncomfortable realizing that the IOWA´s were not as fast as sometimes claimed -though remain to be very fast vessels by any standart- but I argue from the base of trial data, not from anecdotes. The same methodology applies to RICHELIEU´s data, which again, are based on trials, not on anecdotes. I outlined the differences of the trial conditions already but data is what I have to work with, so be it.
That speeds patterns change in the vessels lifetime period through different conditions and modifications is nothing uncommon and I do not lay claim to support the idea it didn´t happen.

You should take into consideration the particulars of the sea/air on the particular day/days of the test/s. Differences of more than 1kts are known to appear between tests done in shallow/deep water, or between tropical and temperate waters, etc.

I know. If anything, the cold, deep water off Rockland Maine would have benefitted NEW JERSEY compared to trials conducted by RICHELIEU in different seas. NEW JERSEY conducted her trials at generally deep enough water to exploit 32 kts or more but it didn´t happen.

alecsandros
Senior Member
Posts: 3992
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania
Contact:

Re: Fuel consumption Bismarck

Postby alecsandros » Fri Jan 20, 2012 1:17 pm

Good info as allways, Delycros.

What I would like to underline is that a battleship's speed can vary with up to +/-3 kts in various conditions, not including bad weather and storms (Scharnhorst may have been slowed by as much as 6kts during the battle of North Cape by the waves...). Richelieu for example may have been able to reach 32kts in her finalized profile (her sistership JEan Bart mantained 32kts+ for 2 hours according to G&D) in a temperate climate. However, in tropical conditions the ships failed to reach 30kts (again, according to G&D). Maximizing the load also reduces speed, in some designs faster / 1000 tons, in others slower (the North Carolina's were considered to gain 0.25kts/1000 tons of reduced load if I remember correctly)
Thus, Richelieu in tropical waters at 47.000tons would probably reach a maximum of 29kts, and possibly even 28kts (my own estimate...).

So much for relativity of the measurements.

I'd like to add Vanguard as a possible challenger for fastest BB ever built: according to G&D, the ship obtained 31.57kts @ 136.000hp @ 45.500 tons (a very light displacement for this ship). 30.38kts were obtained at close to maximum load, and similar power outputs. What I find remarcable is the reduction of only 1.19kts coming from maximizing the load (from ~ 45500 to ~ 51500t).

-----

Most interesting the lack hard data of 32kts+ speeds of ships of the Iowa class!

However, what about the Nowaki's chase at high speed ? I udnerstand the pitometers of the 2 battleships recorded 32.5kts...

Thanks,
ALex

delcyros
Member
Posts: 213
Joined: Mon Feb 07, 2011 9:26 pm

Re: Fuel consumption Bismarck

Postby delcyros » Sat Jan 21, 2012 7:27 pm

The ten datapoints of USS NEW JERSEY´s 1943 trial results for 56,200 to 56,800ts displacement result in the following MMF model curve:

010000 SHP = 12.6kts (extrapolation)
016470 SHP = 15.3kts (primary data, trial)
016800 SHP = 15.5kts (primary data, trial)
020000 SHP = 16.4kts (interpolation)
030000 SHP = 18.7kts (interpolation)
038000 SHP = 20.0kts (primary data, trial)
038340 SHP = 20.0kts (primary data, trial)
040000 SHP = 20.5kts (interpolation)
050000 SHP = 21.9kts (interpolation)
060000 SHP = 23.1kts (interpolation)
070000 SHP = 24.1kts (interpolation)
078000 SHP = 24.9kts (primary data, trial)
080000 SHP = 24.9kts (interpolation)
081900 SHP = 25.1kts (primary data, trial)
090000 SHP = 25.7kts (interpolation)
100000 SHP = 26.3kts (interpolation)
120000 SHP = 27.5kts (interpolation)
126400 SHP = 27.9kts (primary data, trial)
140000 SHP = 28.4kts (interpolation)
160000 SHP = 29.2kts (interpolation)
163400 SHP = 29.3kts (primary data, trial)
170960 SHP = 29.7kts (primary data, trial)
180000 SHP = 29.9kts (interpolation)
200000 SHP = 30.6kts (interpolation)
212000 SHP = 30.9kts (rated design power)
220000 SHP = 31.1kts (interpolation)
221030 SHP = 31.0kts (primary data, trial)
240000 SHP = 31.6kts (extrapolation, max. power 1 -without cavitation)
254400 SHP = 31.9kts (extrapolation, max power 2 -assuming no cavitation takes place)
----------------------------
Higher speeds would be possible at lower load. Main issue with these data is that performance is somehow overstated at speeds in excess of 30kts but the error margin is + 0.15kts. One digit data, only.
----------------------------
Given the data we know from the three ships mentioned:
BISMARCK for displacements at 75% load
RICHELIEU for displacements at 25 to 50% load
and NEW JERSEY for displacements at 80 to 85% load

and assuming that the relevant rated powers (100% output) are:
134000 SHP for BISMARCK
150000 SHP for RICHELIEU, and
212000 SHP for NEW JERSEY

it´s possible at least to draw comparative performances for these respective loads (that is unaccounted for load differences, using trial reference as the only source), comparing the speed with the powerload (1% output to 120% power):

Image

note that differences in displacement are unaccounted for. The IOWA class appears to be less efficient at very high speeds or else, RICHELIEU and BISMARCK are more efficient. The reasons for this I am not intending to explore, but I guess that lower propulsive efficiency caused by the close neighborhood to cavitation limits may in part be interesting to investigate.

Byron Angel
Senior Member
Posts: 730
Joined: Sun Mar 06, 2011 1:06 am

Re: Fuel consumption Bismarck

Postby Byron Angel » Sun Jan 22, 2012 4:03 am

Delcyros,

US fast battleships were built with "bulbous bows" (also featured in YAMATO IIRC) as a result of lengthy hull form testing earlier in the century by Taylor. My understanding is that the bulbous bow reduces resistance at mid to high cruising speeds (reducing fuel consumption by as much as 5 pct). The value of this design feature has been confirmed by its wide application in modern merchant ship designs. Some sources assert that it provides reduced hull resistance throughout the upper end of the speed regime, but I am not certain on this point; it contradicts material I have read in connection with its merchant ship use.

An additional benefit of the bulbous bow to the US fast BB designs was that it provided additional buoyancy well forward, which helped to counteract the effects of their otherwise very fine lines forward.


B

delcyros
Member
Posts: 213
Joined: Mon Feb 07, 2011 9:26 pm

Re: Fuel consumption Bismarck

Postby delcyros » Sun Jan 22, 2012 2:29 pm

As far as I know, the TAYLOR bow is nothing unique to US fast BB's .
The HIPPERs, the Twins and BISMARCK class -also DUNKERQUE and RICHELIEU- all had this feature to reduce drag and provide additional buoyoncy fwd.

The BREMEN and EUROPA both had a bullbows bow with a very prominant shoulder.
The hollow lines fwd between ow and shoulder improved the drag but caused the ships to be notoriously wet.
Thats well documented for french and german ships and for SOUTH DAKOTA class at least in one case, too.

User avatar
Dave Saxton
Supporter
Posts: 2890
Joined: Sat Nov 27, 2004 9:02 pm
Location: Rocky Mountains USA

Re: Fuel consumption Bismarck

Postby Dave Saxton » Mon Jan 23, 2012 2:27 am

alecsandros wrote:Most interesting the lack hard data of 32kts+ speeds of ships of the Iowa class!

However, what about the Nowaki's chase at high speed ? I udnerstand the pitometers of the 2 battleships recorded 32.5kts...

Thanks,
ALex


Muir wrote this was the case. However, Brad Fischer found the original document in the National Archives several years ago and reported on it, and it was 30kts or 31kts (I don't recall exactly) and a fraction according to document not 32.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.

alecsandros
Senior Member
Posts: 3992
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania
Contact:

Re: Fuel consumption Bismarck

Postby alecsandros » Mon Jan 23, 2012 7:44 am

Ah, thanks Dave!

This corresponds well to Friedman - US Battleships - "the Iowa class obtained a maximum of 30.7kts in tropical waters and with bottom fouling"

dunmunro
Senior Member
Posts: 3118
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: Fuel consumption Bismarck

Postby dunmunro » Mon Jan 23, 2012 9:59 pm

Dave Saxton wrote:
alecsandros wrote:Most interesting the lack hard data of 32kts+ speeds of ships of the Iowa class!

However, what about the Nowaki's chase at high speed ? I udnerstand the pitometers of the 2 battleships recorded 32.5kts...

Thanks,
ALex


Muir wrote this was the case. However, Brad Fischer found the original document in the National Archives several years ago and reported on it, and it was 30kts or 31kts (I don't recall exactly) and a fraction according to document not 32.


I have some excepts from the Admiral's and Iowa/New J. action reports and the highest speed mentioned is 31 knots in the Admiral's report and 30 knots in the ship's action reports. No mention of higher speeds on USN vessels.

alecsandros
Senior Member
Posts: 3992
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania
Contact:

Re: Fuel consumption Bismarck

Postby alecsandros » Tue Jan 24, 2012 9:40 am

I can't stop fantasizing about a battleship 1000 mile-race.
Iowa, Richelieu, Tirpitz, Scharnhorst, Vanguard, Vittorio Venetto, all lined up at the starting line... With minimum possible loads... And clear bottoms...
3..2..1.. START!

The race would show both the realistic maximum speeds of all ships in the same circumstances (water temperature, depth and density, sea condition, etc) AND their acceleration curves... And, very importantly, the durability of their boilers and turbines...

My bet would be on the Iowa... But that's just my opinion.


Return to “Naval Propulsion”

Who is online

Users browsing this forum: No registered users and 1 guest