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Opposed piston engine
1303Steve - March 19th, 2011 at 01:10 PM

Hi

This is pretty amazing This is no wimp engine.
It's a two cylinder with four pistons delivering 300+ Horse Power It's extremely small and very efficient and is presently in use in test applications

The configuration below is equivalent to a extremely ballsy four cylinder engine When doubled, it's an extremely ballsy 600+ H.P. engine

It's called OPOC (Opposed Piston Opposed Cylinder), and it's a turbocharged two-stroke, two-cylinder, with four pistons, two in each cylinder, that will run on gasoline, diesel or ethanol. The two pistons, inside a single cylinder, pump toward and away from each other, thus allowing a cycle to be completed twice as quickly as a conventional engine while balancing it's own loads.

The heavy lifting for this unconventional concept was performed Prof. Peter Hofbauer. During his 20 years at VW, Hofbauer headed up, among other things, development of VW's first diesel engine and the VR6.

The OPOC has been in development for several years, and the company claims it's 30 percent lighter, one quarter the size and achieves 50 percent better fuel economy than a conventional turbo diesel engine.

They're predicting 100 MPG in a conventional car.
For a good demo, See:
http://www.engineeringtv.com/video/Opposed-Piston-Opposed-Cylinder 


annosL - March 19th, 2011 at 02:13 PM

Interesting, that was 2008, wonder how it's going now(bit long for a Dub)


vwo60 - March 19th, 2011 at 04:43 PM

Its an old concept with many engines already built using this disign, the commer knocker diesel engine from the 50's, the Napier deltic engine that was first used in marine applications and then adapted for use in diesel electric locomotives and the Doxford marine deisel used in large ships, also used as aircraft engine's by the germans.


Old Hutcho - March 19th, 2011 at 07:02 PM

Ah yes. The Germans!:lol:


68AutoBug - March 19th, 2011 at 08:41 PM

Hi vw060,

Yes,
the COMMER knocker engine in rootes group trucks in the 60s had an engine that started design in a German WW2
bomber....

never really knew much about them...

heard they were a two stroke diesel???

they were well liked in the Country areas...
don't know about the cities...

cheers

Lee

Steve
Now 100 MPG would be great....
even 50 MPG lol... Lee


oldtub356 - March 19th, 2011 at 11:35 PM

vwo60 - You bring back fond memories - I spent 2 years on a General Cargo (pre container era) ship running a Doxford.
Some specs:
7 cylinder, 14 piston, vertically in line above the crank, x3 crank throws per cylinder, 1500hp per cylinder, about 25 metres long, x3 injectors direct into the combustion chamber @ 7000PSI, bore - just under a metre, stroke - nearly 20 feet, maximum revs 105 but don't dwell around 90rpm for too long - harmonics break the crank - sister ship sunk due to big end going through the keel. No turbo, but a single scavenge piston to one side of the engine, about 3 metre bore and 0.5 metre stroke running at about 10 time engine revs. Engine starting, x3 huge air tanks holding 600psi, pump it into the appropriate cylinder to make the engine start ahead or astern.
More or less an on-board dyno system: A barrel dyno chart could be connected to any combustion chamber to provide a gas pressure loop and the injector pump adjusted for mixture. To measure actual horsepower, a transformer (AC - the ship was 220volt DC) was wound on the Prop shaft and the phase shift caused by the shaft twist between the two windings was measured and HP calculated - sorry to bore you.

Anyway - want a modern engine? Check out this baby:

http://www.physorg.com/news/2011-03-msu-prototype-video.html 


HappyDaze - March 20th, 2011 at 07:33 AM

C'mon Lance, don't hold back. We want ALL the specs, not just a few snippets! You know - BMEP, etc, etc.


vwo60 - March 20th, 2011 at 07:57 AM

oldtube356,
It also brings back memories and they are not fond, i have the mispleasure of reringing one of those heaps of XXXX,
I remember it had .181" wear in the bore, these were made in melbourne under licence from the Poms, now days i work offshore on far more modern equipment, gas turbines and modern marine deisels and assosiated oil and gas process equipment


vlad01 - March 20th, 2011 at 10:40 AM

have you seen the revetec engine. its a crankless design, very well balanced and so far is up to 39.5% efficiency on petrol.
No crank shaft, no side load, no side to side reciprocating weight. Brilliant!

oh yeah and the current proto type is pushrod :lol: doesn't need anything more if the pistons only reciprocate like 1000 time a min.

http://www.revetec.com/gallery_x4v2_01.htm 


oldtub356 - March 21st, 2011 at 01:21 AM

If I give you too much Greg, I'm sure that you will be tempted to try'n slot one in, over the swing axles - AAh alright, just a bit - fuel consumption is measured in tons per day - imagine that fuel gauge on the dash.

vwo60 Yes, I lent a hand doing a re-ring in dry dock in HK - the third Engineer was short and 17 stone, so had problems fitting inside the bore with his ladder and grinder to remove the lip - it's amazing what favours got called in from a skinny electrician. I had the same attitude toward the UK ships and cars - little wonder that both industries failed when compared to innovations elsewhere.
Amazing engineering innovations in your area of business over time - I like to visit the Sulzer site and have a 'perve' on their latest.

All of that modern engineering in your life yet still into Dubs - now that's luurve!!


Lucky Phil - March 21st, 2011 at 06:38 PM

The junkers diesel that ran german tanks in the desert in the second world war ran a similar setup. They were designed to run in the desert and never missed a beat. Funny thing was, take them out of the desert and they didn't want to run.


bajachris88 - March 21st, 2011 at 06:43 PM

The great thing about these engines, includingv the commer is that although this engine has 4 pistons, it still only has 2 cylinders meaning you only need to pay the appropriate rego for the 2 cylinder class :tu:
CHEAP! :)

Only issue is it being 2 stroke... You could make it work but they have narrow power bands