The Waissi Engine

[RustyLugNut]

Originally Posted by P-hack

I mean for a given displacement, the 8 cylinder is less efficient than the 4.

Yes if it can reduce engine friction by %50 (which is 10-20% of engine only losses) that would be a 5-10% increase in efficiency in itself.

less moving "parts" is good too.

Not sure about the change in piston motion, how that plays out.

see also double acting scotch yoke:
Patent US20120272758 - Double-acting scotch yoke assembly for x-engines - Google Patents

That would result in a motion that would parallel the old radial engines Old Mech brought up in another thread. However, this configuration would be much smaller and lighter. I could see this in an aeronautical application such as light planes and remote piloted vehicles. Compact, light and fuel efficient - it seems like a good match.

[P-hack]

I don't think so re: radial motion.

http://www.youtube.com/watch?v=I5ZwxzSrrO0&NR=1

[jeff88]

Originally Posted by Frank Lee

Jeff, there have been many, many horizontal cylinder engines before this one came along- go look at your lawn mower. Cylinder lube is just fine.

It would be very, very strange if they ever thought of building this layout with an odd number of cylinders.

I'm not disputing the quantity or quality of horizontal engines, I just don't know how the lubrication process works in them. Do you know how that works or have any literature for me to thumb through?

It would indeed be strange for an odd number, but I was alluding to why only certain even number cylinders would work. I forgot about all the axes that need to be balanced, not just the horizontal.

[Frank Lee]

They're lubed by splash. I think the crankcase has such a whirlwind in it that cylinder orientation doesn't matter when it's running. About the only concern I'd have special to horizontal cylinder is when it's off, to make sure that a piston isn't submerged in oil thus potentially leading to hydraulic lock-say, if my Gold Wing fell on it's side and a month later I righted it and tried to start it. But oil level is normally much lower than that in the crankcase.

I said it would be quite unlikely to have an odd cylinder count because they'd have to have one piston without it's opposing counterpart.

[RustyLugNut]

Originally Posted by P-hack

I don't think so re: radial motion.

The external configuration and similar piston dynamics in a smaller package is what I was referring to.

[user removed]

How about a rankine cycle with one of these as a compressor and the other for power, like a jet engine.

My first post on this forum had this illustration.

Animated Engines - Gnome Rotary

regards
Mech

[user removed]

Now reverse the pistons and cylinders with the cylinders revolving around the journal, with the pistons connected to the outer rim, without connecting rods. No reciprocation and a balanced rotary engine, a true rotary that acts as it's own flywheel. This one in the video is spinning at 2k RPM (aproximately) and it is sitting there not securely connected to anything with about 10 pounds of mass spinning at that speed.

Even opposed piston engines are still reciprocating and even with multiple cylinders they still have balance issues. The only thing holding this engine in place is my hand.

http://www.youtube.com/watch?v=2BQwBGKxShk

The Wassai is still reciprocating, still has counterweights on the crankshaft, still has poppet valves, and now has cam to piston connection sliding issues and rapidly changing inertial forces.

regards
Mech

[user removed]

Extensive reading but interesting to those who pursue the history of technology. Many of the "Newest Innovations" are merely ancient technology repeated.

The Museum of RetroTechnology

regards
Mech

[NeilBlanchard]

It would be good to avoid poppet valves, I agree. It's a difficult challenge to work with the sporadic pumping and the reversing pressures.

Do you folks remember this engine?

Directory:Revetec Cam-Drive Engine - PESWiki

The major advantage of the Revetec engine is that the motion of the piston is controlled by the designer. The geometry of the Waissi engine are like the geometry of a connecting rod engine - fixed by the design.