March 5, 2019

"German" Diesels to be on Australia’s future Attack class submarines

ARTICLE

In a notable article INDAILY Adelaide’s independent news, February 21, 2019 reported :

That Jean-Michel Billig, Executive Vice President, Future Submarine Program [Naval Group] and Member, Naval Group Executive Board in translation, made the very significant comment that:

“Diesel generators [for Australia’s future Attack class submarine] will be German...”

COMMENT

[At 4,500 tonne (surfaced) the Attack class submarines will probably need to achieve a diesel output of 6,000kW requiring at least 4 x 1,500kW diesels]

From the "will be German" diesel statement Anonymous [with some further translation by Pete into more correct English] on February 27, 2019 calculated Australia’s future Attack class submarines may use the following German diesel designs:


       specifically the MTU 12V 4000 (mechanical output=1300kW
       Mean Effective Pressure (Pme) = 27.9MPa [1])

OR
B.  MAN Energy Solutions (MAN based in Augsburg, Germany)  formed 2010 from merger of
      MAN Diesel and MAN Turbo.
      specifically the MAN 12 PA4 V200SMDS (1330kW, 25.8MPa).
Note that the MAN 12 PA4 V200SMDS has a slightly lower Pme and a longer but lower rotation or piston speed (1300rpm, 9.1m/s) than the MTU 12V 4000 (1800rpm, 11.2m/s). But if the 12 PA4 V200SMDS is modified (such as common rail injection system), it may achieve about 1500kW of mechanical output by 10% increase in Pme. Higher boost modification depends on the selling price.
It is unlikely the older MTU 16V396 will be used as its Pme is low at 20.5MPa.

[1] see Mean effective pressure (Pme) is a valuable measure of a reciprocating engine's capacity to do work that is independent of engine displacement. Higher Pme means better performance. Pme = 8 x E / (3.14 x N x S x D^2 x H). Where, Pme = brake mean effective pressure, E = mechanical output, N = number of cyliders, D = cylinder bore, H cylinder stroke.
PETE COMMENT

Penske Power Systems supplies MTU and MAN diesels for marine and defence applications in Australia with branches all over Australia including Adelaide (where the Attack class submarines are being built).

Anonymous and Pete

3 comments:

Anonymous said...

Hi Pete

To achieve total 6MW (=6000kW) of electrical output, 6 diesel generators (GEs) are needed [1]. As SAAB-Damen submarine (beam 8m) for Warlus Replacement equips with three GEs (MTU or MAN) arranged in parallel, Attack-class (beam 8.8m) can equip with 6 GEs consisted of 2 parallel arrangements with 3 GEs[2]. Length of Japan(J)-SEA1000 submarine without AIP and 4 GEs is 90-92m, and then unless Attack-class equips with AIP, its length may be as same as J-SEA1000 submarine (90-92m). 97m of length for Attack-class may suggest equipment of AIP.

Following is just a suggestion. In the case of 100MW AIP and 6MW GEs, indiscretion ratio (IR), the perfance indix of diesel submarine is very roughly estimated to be 3% [3], and in the case of non-AIP it may be 4-5%. It’s not bad.

[1] MTU V12 4000 (mechanical output 1300kW, electrical output 1040kW)
MAN 12 PA4V200 SMDS MT V12 4000 (1330kW, 1064kW)

[2] Estimated cross section of Attack-class from various pictures: diameter of pressure hull (d) = 8.8m, thickness of hull steel (a) = 0.05m, thickness of sound absorbing rubber (b)= 0.10 m, width of hull stiffner ring (c) = 0.25m, width of diesel (f) = 1.7m, average distance between diesel-diesel or diesel – hull stiffer (Y). Then, Y=(d-2a-2b-2c-3f)/4= (8.8-2x0.05-2x0.1-2x0.25-3x1.7)/4 =0.72m.

As Y=0.4m for Warlus-class (3DEs in parallel) and Y=0.5m for SAAB-Damen submarine (3DEs in parallel), 3DEs in parallel for Attack-class are a physically possible arrangement.

[3] Calculation in the case of 100MW AIP and 6MW GEs
(1)AIP: 100MW
(2)Energy consumption per day ca.6MW =[hotel load (180kW) + propullsion 60kW] x 24 hours
(3)Operation 10 weeks = surveillace 7weeks (ca.50days) + transition 3weeks (ca.20days)
(4)Required battery energy per day for suveillance = Energy consumption per day – energy suppled from AIP = 6MW-100MW/50days = 4MW
(5)Charge period = (4)/electrical output of GEs x 1hour =4MW/6MW x 1hour = 0.67 hours
(6)IR = charge period (hours) / 24 (hours) x100 (%) = 2.8%=0.67/24 x 100 =2.8%

Regards

Pete said...

Hi Anonymous [at 7/3/19 11:19 AM]

Thanks I will turn your information into an article next week.

Regards

Pete

wispywood2344 said...

Hi Pete

I think that the BMEP calculation in this article is incorrect.
For example, the actual BMEP of the MTU 12V 4000 series is about 2 MPa. [1]

[1]http://www.genpowerusa.com/content/files/1600-KW-MTU-GENERATOR-BCMU1600S-60T2.pdf#page=2

Regards

wispywood2344