Deltic Diesel
 

Ran across this picture of myself standing beside a Deltic Diesel at the Railroad Musuem in York, England. Thought those not familiar with the engine might be interested in a picture of a really creative diesel. Three crankshafts, all cylinders, no heads.

And very heavy too! Notice the pistons aren't evenly timed, the exhaust piston is a few degrees ahead of the intake piston.

http://upload.wikimedia.org/wikipedi...tion_large.gif

I think the weight per piston is probably less than an in-line or V engine. Can't remember how many pistons that engine had but it must have been 24 or 36 I think. I think overall, the weight to horsepower ratio of a Deltic diesel is pretty good.

Okay--

I'm moderately fascinated..

Doesn't the engine create a heat differential between the "intake" and "exhaust" piston?? Seems like the intake side of the engine wouldn't heat as quickly, and would cause fatigue issues-- maybe not..

Do they tie the cranks together with a chain, gears or what??

Were these USED in something-- or were they strictly an experimental engine??

Used in trains and boats too I believe. If you go to youtube, you can search for "deltic" and see and hear some clips of a deltic powered train.

They were used in the British Railways class 55 "Deltic" trains, which were in use on high speed express services until being replaced by the Inter City 125, or HST. As a locomotive power unit, it was very light.

http://en.wikipedia.org/wiki/Napier_Deltic

The Deltic engine makes an amazing noise, they are really distinctive.

I did some track testing and stress analysis work on the 125s, to find the root cause of some suspension failures, and can vouch that they can actually go much faster than 125!

http://en.wikipedia.org/wiki/Inter_city_125

The Deltics were withdrawn from service in the early 1980's, and of the 22 which were built for BR, 6 survive in various states of preservation.

We are now approaching the point where the HSTs are to be withdrawn from service, and it's very sad to say that the work has not been awarded to the only remaining UK train builder - the work has gone to Hitachi!

While I'm not mad keen on protectionism, it seems like madness that we aren't building our own trains any more.

Cranks are geared together on the back of the engine. Don't know about the heat differential.

The 2 pistons running at different temperatures isn't a big deal - it could be argued that each piston, whether intake or exhaust would see a smaller range of temperatures than if it were installed in a conventional engine.

There was also a much smaller engine working on a similar principle to one arm of the Deltic, the Rootes TS3, which saw considerable use in Commer trucks in the UK.

http://www.feweatherill.com/engine/ROOTES_ENGINE.htm

That is facinating!!!!

Junkers opposed piston diesel aircraft engine:

http://en.wikipedia.org/wiki/Junkers_Jumo_205

Its a two stroke engine with more moving parts. Would it be lighter than an in-line three cyl engine...well the three cyl engine would have to have a longer stroke, but it would accomplish the same thing wouldn't it?