SUBSIM Kiel meet

[Jimbuna]

Originally Posted by CORONER

Any more Fotos from this meeting?

I have now registered but do not see more than before.

Try sending a PM to elanaiba, Catfish or Schroeder.

Welcome to SubSim

[Catfish]

@ Elanaiba,
have found a photo with a crewmember actuating the clutch for coupling the electric engines to the propshaft, but it's pretty bad (it is from one of Buchheim's three photo books). It is a simple hand wheel..

[Aktungbby]

Originally Posted by Catfish

@ Elanaiba,
have found a photo with a crewmember actuating the clutch for coupling the electric engines to the propshaft, but it's pretty bad (it is from one of Buchheim's three photo books). It is a simple hand wheel..

[QUOTE]A chief mechanician prisoner, claiming expert knowledge of Diesels, gave the following explanation of the term "Diesel-Electric." "Diesel-Electric" propulsion is used, when it is desired to put one Diesel out of action for repairs or other reasons, and it is nevertheless required to turn both screws. The electric motors are dual-purpose motors. They can be used either as dynamos or as generators as required. The switching over from one use to the other is done by means of a switchboard and a series of resistances. The whole procedure takes but a few seconds. If it is required, for example, to stop the port Diesel and keep under way on the other Diesel, the starboard generator is started from the batteries. The compression cocks of the starboard Diesel are opened, the generator slowed down and the clutch slowly let in, thus turning the Diesel engine. The cocks are then shut and the Diesel will run under its own power. The dynamo is then switched off and the speed of the Diesel increased so that the starboard generator produces enough electricity to drive the port dynamo. The electricity produced is led through the batteries to prevent the current fluctuating. The following table, found among captured documents, would therefore, indicate that if one Diesel is turning at 285 revs. at slow speed and the electric motor is coupled with it, the number of revs. is reduced to 240; the electricity produced is sufficient to turn the other screw at 155 revs. The loss in revolutions is due to the loss of power in the process of conversion. The differences in speed between port and starboard propellers is counteracted by the rudder. http://www.uboatarchive.net/U-570/U-570INT.htm Below is revs differential 'twixt diesel and electric 'clutched' revs:

.

Revs.

Speed in Knots.

Revs.

Speed in Knots.

Speed in Knots.

Diesel Revs.

Electric Motors Revs.

Slow

285

10

114

3

7.5

240

155

Half Speed

350

12

167

4.5

9

285

195

Three-fifth speed

390

14

220

6

10

330

215

Four-fifth speed

460

16.5

275

7.5

11

360

240

[Catfish]

^ Nice!
Not as Diesel-electric as in the US fleet subs, but the first time i read about this, and in detail!

Should post this in the Wolfpack forum, so they can build this sim right!
But maybe a bit too complicated to simulate all this

What should be simluated though is, while both Diesels running full ahead and both driving the generators (= both electric engines switched to generator/dynamo mode and coupled to the propshaft), the overall speed should change from say 18 knots to a bit less, but not decreasing the overall speed so much as it has been simulated in all those other sims!

Running full ahead while charging the batteries should still be good for some 15 knots!

Originally Posted by Jimbuna

Try sending a PM to elanaiba, Catfish or Schroeder.

Welcome to SubSim

thank you. Though I don't believe they would answer me. They don't know me.

[Jimbuna]

Originally Posted by CORONER

thank you. Though I don't believe they would answer me. They don't know me.

On the contrary, I think you'll find they are quite amiable gentlemen.