Revolutionary Engine Debuts @ Miami Show

Does this mean all four strokes (intake, compression, power and exhaust) occur in each revolution?

I can't picture that. A four stroke needs two revolutions to complete all four strokes. Or is this what the 'main cam' is doing (unlike a cranksaft)?

I think what they are refering to is that each piston in a normal 4 stroke fires every two rev's of the crankshaft, because this engine has double ended pistons, each piston can effectivly fire every rev'.

At the risk of sounding a little crude, one end is "s u c k - squashing" while the other end is "bang - blowing" (s u c k , squash, bang, blow = 4 stroke )

Fuel Type?

Maybe I missed it, but I've not been able to determine the fuel type for this engine. Can it use diesel rather than some more highly explosive fuels that we don't care for on boats?

It says 'multi-fuel use' so that could include JetA, kerosene, biodiesel, etc. as well as gasoline. Where was that booth? I walked all over the convention center inside and out and I didn't see it.

The intercooled turbo motor will find many different applications, especially in the 20'-30' range. Look out Mercury!!

I knew it was an oldie, I just didn't have the heart to tell 'em

John's question hadn't been answered, so I thought I'd have a go, just incase he was still interested.

Multi-Fueled definition

I beleve the term 'multi-fuel' is possibly overused here, and it does not always refer to the total available fuel spectrum. Diesel fuel usage usually requires some substantial higher compression ratios so as to not require an ignition source. I think I detect an ignition distributor in the photos. And I don't know of many, or any certified diesel fueled small aircraft engines.

If they appeared at a marine show, one would think they would most definitely pronounce the use of diesel fuel, which they do not to my knowledge....just my observation

3 years later... a Diesel.... and some other activity.

"......NEW DIESEL / MULTI FUEL ENGINES

We are in the final stages of dynameters test trials performance data gathering in Detroit on our prototypical 8 cylinder, 7.2, 352HP "Work Horse" diesel /multi fuel engine which produces 1,140 ft lbs of torque.

This engine and the Gas-Cam engine share many common design features. A sinusoidal cam rather than a crankshaft was used to convert the linear motion of the pistons into rotational motion in the drive shaft. The engine contains substantially fewer parts and therefore is much lighter than an equivalent conventional engine. This engine has a very high torque of 3.2 ft-lb per HP. This is 75% greater than an equivalent displacement 7.2 liter 6 cylinder Caterpillar diesel engine. The fuel performance is also better than the Caterpillar. This AVE engine is designed for 40,000 hours of operation between major overhauls. If this engine was placed in a truck, and it was driven at 50mph, you could expect to travel 2,000,000 miles before the next overhaul or 75 trips around this planet. A Digital Signal Processor manages this engines performance. There is a number of interesting new features design into this new AVE engine....."


http://www.axialvectorengine.com/about_history.html


And after all this time there's something going on.
http://www.sec.gov/Archives/edgar/data/1144130/000111776807000162/mainbody.htm

Revetec Engine

Here's another very interesting engine without connecting rods. WHen I first read the description of the Dyna-Cam engine I was picturing the opposed piston arrangement of the revetec engine.


I brought this subject up under the "Air-Electric Drive" posting at:
http://www.yachtforums.com/forums/35854-post35.html
...but no one responded


Revetec Engine
http://www.revetec.com/
http://www.revetec.com/development.htm


Here is another forum discussion with more reference websites:
http://www.boatdesign.net/forums/showthread.php?t=9878

I wonder which arrangement might last longer, the sinusoidal cam/crankshaft of the Dyna-Cam verses the “trilobate” (three lobed) cams of the Revetec??

Thanks Brian.
I have not looked at the "Air -Electric Drive" thread for a while. Seemed to be a lack of consensus as to the utility/reality of that system.
The Dynacam at least has been shown to work. Last night I realised that I hadn't heard anything about it for a while so looked back and found this old thread.


" I wonder which arrangement might last longer, the sinusoidal cam/crankshaft of the Dyna-Cam verses the “trilobate” (three lobed) cams of the Revetec??"

I've thought about this as well in regards to the Dynacam. In conventional diesel engines the maximum stress/wear points in the system have long ago been identified and dealt with, more or less, by materials/lubricant developments. I don't know if there are higher forces present between any of the faces in the Dynacam or the Revetec than have already been dealt with in conventional diesels or even if the materials/lubricants are really issues.
I would be surprised if some of the major manufacturers of engines have not built a mule or three of these engines and come to their own conclusions. The chances of that information being available outside those companies is slim to none.
The "not invented here" factor as a reason for not looking at different technologies is for the most part a thing of the past. I've heard the conspiratorial "bury the technology" story too many times and now just refer to the investments in Ballard that the automotive industry has made to zero that one.

I still have great reservations about that myself...just seems to go against all physics we learned.

I've followed this Revtec development for awhile, but not as throughly as I would have liked to (I still have a bunch of related forum discussions from some knowledgeable engine folks on my computer that I've not had time to read yet). One thing I've noticed over the period of time is their addition attention to the rollers/trilobate cam interfaces. so there must be extra wear problems they are finding and addressing. I don't believe this has been fully addressed on the dynacam engine. what bothers me is "trunion rollers are housed in the middle of each piston that ride along the cams". Their claims of '2 million miles' seem unfounded to me.

Remember in both of these cases the cam following bearings and cam faces are having to absorb the power of the iginition explosion rather than just being conventional valve activation units as in conventional engines.

I really do try and keep an open mind about new technologies and developments. Have had a lifelong passion for machines. For some reason many of those claiming to have new technologies make statements that just make it very difficult for me.
"This AVE engine is designed for 40,000 hours of operation between major overhauls. If this engine was placed in a truck, and it was driven at 50mph, you could expect to travel 2,000,000 miles before the next overhaul or 75 trips around this planet."
This is a perfect example. Real world, what truck actually runs at 50mph?
That sort of statement immediately makes me more than a little bit suspicious.
Run a 671 at a constant load at optimum speed and the darn thing could probably circumnavigate the solar system if the roads were there. Who gives a ****? Motors just don't get that kind of a life.
End of rant.

Brian, I agree with you on the trunion rollers in the Dynacam. They are getting the bejesus whacked out of them. Have they looked at ceramics to lower the mass? Have they looked and then found out that the costs of the materials required to deal with the problems make the whole deal a non-starter except for the military? Too many questions and not enough answers.