Steam generator exhaust port, T1-G7a - Info needed

[jsl]

Hello people,

I've got a somewhat exotic question, but I hope some of you know the answer. Perhaps our german members?

This question is directly linked to a little off-time project I'm toying around with. Propel-powered torpedoes already exist in the RC-sub universe, but propel powering a propped torpedo is an interesting project. This is where the exhaust port question comes into play.

The WW2 German T1-G7a powerplant was apparently a 235 hp steam powered 4-piston engine. This powerplant gave it both excellent range and speed capabilities, on the drawback that it left a visible bubble trail in its wake.

What I'm trying to learn, is how the spent steam left the fish. Did it escape along the shaft and the props whipped the steam into tiny bubbles? Did the fish have just a single exhaust port located in the side? Did it have a whole array of tiny holes in the rear part?

I would be very happy if someone could provide the answer, a torpedo layout, or point me in the direction of someone that maybe know the answer.

Thanks in advance!

[anonymous]

Hi Jacob,

I don't have the

Hi Jacob,

I don't have the complete answer - just looked up topic in a book 'The Devils Device - Robert Whitehead and the history of the torpedo.'

'Steam' is a bit of a misnomer - wet combustion products is perhaps more like it - using a heater. (Concept came from Whitehead and was used by most Navies))

The G7a was introduced in 1937 but was rapidly replaced by electric torpedoes. It was 21" in diameter, had a range of 15000 yards and a speed of 44 knots.

Book is very short on drawings so I don't know where the gases exited. Over to someone else?

David

BTW Apparently Japanese torpedoes were some of the best in WW2 with a range of 18 nautical miles!

[mkeatingss]

I believe that the German

I believe that the German torpedos had the same exhaust system as their American counterparts. The exhaust went out the screw shaft. If you run across an old torpedo memorial, you'll notice a large hole in the center of the screw shaft, that's the exhaust.
Mike K.

[JWLaRue]

That is how I understand

That is how I understand it as well. The "steam" exhaust exits through the screw hub. Here is a photo that I took during my recent visit to the U-505. The exhaust port can be clearly seen in the center of the prop]http://img185.imageshack.us/img185/6953/img11943dk.jpg[/img]

A good place for drawings of the German torpedoes can be found in [i]Anatomy of the Ship #3] by David Westwood.

-Jeff