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Catfish · 04-17-08, 09:59 AM

Hello,
with increasing rpm of the Diesel, and thus the generators, loading will be faster, ok.
But there is a small mistake in SH3 right from the beginning - in a real german U-boat you would not have to stop one propellor to charge the batteries. This is completely different to the US approach used in their submarines.

The power line in a U-boat was Diesel - propshaft - propellor.
The electric engines sit "in the middle", at the propshafts. If you use the electric engines, the Diesel(s) is/are unclutched, and the Electric engines are clutched (or coupled ?) to the propshaft.

When the boat surfaces, and wants to charge the batteries, the Diesel is clutched to the propshaft. The electric engines are still clutched to the propshaft, but now electrically switched to charge the batteries - the electric engines serve as dynamoes.

So a U-boat would run at flank with both propellors turning, and still charging the batteries - however flank speed of say 18-19 knots was reduced to 15/16 by the effort to turn the dynamoes. As soon as the batteries were completely charged, the dynamoes would be unclutched, allowing the propshaft to turn freely again.

A third combination would be to couple the electric engines on the propshafts and add their power to the Diesels. It drained the batteries quite quickly, but the speed was appx. 20 knots depending on the boat, if only for a short time.

Greetings,
Catfish

04-17-08, 09:59 AM	#8
Catfish Dipped Squirrel Operative Join Date: Sep 2001 Location: ..where the ocean meets the sky Posts: 17,767 Downloads: 38 Uploads: 0	Hello, with increasing rpm of the Diesel, and thus the generators, loading will be faster, ok. But there is a small mistake in SH3 right from the beginning - in a real german U-boat you would not have to stop one propellor to charge the batteries. This is completely different to the US approach used in their submarines. The power line in a U-boat was Diesel - propshaft - propellor. The electric engines sit "in the middle", at the propshafts. If you use the electric engines, the Diesel(s) is/are unclutched, and the Electric engines are clutched (or coupled ?) to the propshaft. When the boat surfaces, and wants to charge the batteries, the Diesel is clutched to the propshaft. The electric engines are still clutched to the propshaft, but now electrically switched to charge the batteries - the electric engines serve as dynamoes. So a U-boat would run at flank with both propellors turning, and still charging the batteries - however flank speed of say 18-19 knots was reduced to 15/16 by the effort to turn the dynamoes. As soon as the batteries were completely charged, the dynamoes would be unclutched, allowing the propshaft to turn freely again. A third combination would be to couple the electric engines on the propshafts and add their power to the Diesels. It drained the batteries quite quickly, but the speed was appx. 20 knots depending on the boat, if only for a short time. Greetings, Catfish Last edited by Catfish; 04-17-08 at 10:48 AM.