Double Acting IC Engine

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

That's not really a double-acting design. (No combustion on the rod side of the pistons.)

I think the practical problems outweigh the possible gains.

Is the link actually what you the poster was referring to? Your question was vague at best.

Be advised that Napier Deltic is far from the only OP diesel engine.

Fairbanks produced OP's that were used largely by the US navy many years ago, I later had a chance to run these engines in old offshore tugs. Although very interesting to a gear head like myself, especially the fact that you could run them in either rotation you chose for forward or reverse propulsion, they were not very practical as compared to alternative engines as compared to weight, KW rating, emissions, and maintenance.

Sad to think this but very soon, the only place you will find these is in museums.

Knowing how sometimes words are misunderstood, could this post possibly have been directed to Two Stroke vs Four Stroke engines?

If so, that is a horse of a different color and opens up a completely new discussion.

Tim

Is this what you're looking for? They do exist in actual operation in DG sets...I've worked on them.

Interesting.... I have never worked with one of these, where is the exhaust valves???? By the photo it is a two stroke design.

Tim - It is two stroke diesel and very high compression.

lyn- I am absolutely fascinated by rotary piston engines. I especially love the old prop plane engines where the cylinders rotate around the pistons and the crank is stationary. The cylinders spin with the prop!

That engine started life as an air Austrian compressor, then those crazy Frenchmen decided to bolt one onto the front of an airplane and feed it gas. There's got to be a ton of rotating mass to deal with.

Several aviation museums have them on display.

The Doyle is beautifully machined.

Typical Opposing Piston Engine

Looks sort of like a typical Rotary Engine in reverse form??? But cool none the less.

Interested to see what the poster will come back with.

Tim