Oddball engines and prototypes

[lohring]

Sealing is always the issue with the various rotary valves. A steam engine designer commented there are poppet valves and valves that leak. I observed a rotary valve Crosley 4 cylinder engine that had been converted to overhead rotary valves. I think it used the Cross design. A wealthy friend of my family financed the project. The engine ran fine, but burned too much fuel for its size. The idea was to sell it as an outboard power head. This was around 1960 and the project died.

Lohring Miller

[WilDun]

Looks like all these ideas failed because of the lack of adequate lubrication! and years of research got them nowhere!

I thought well, the piston seems to work ok these days for sealing off the gases, then why not replace these rotary valves with pistons instead! So I delved in to it and came up with a brilliant idea which I reckoned might work and thought, why not use opposed pistons instead!
However I have found that someone else had already come up with the very same idea about 100 years ago! and also some guy down in the Waikato was currently having a go!! (wouldn't you know it!).

So I've had to revise my thinking and I found this stuff which could fix the lubrication problems encountered with those rotary valves in the head, also the (perceived) pollution problem of the two stroke!

https://www.mining.com/platinum-gold...t-metal-world/

This of course could be just a tad expensive, (using Platinum coated with gold) but why not give it a try!- and imagine a cylinder bore coated with the stuff - practically oil free! - of course I have not got the wherewithal to do this (only imagination) - Got to be the answer!

[ceci]

However I have found that someone else had already come up with the very same idea about 100 years ago:

That tends to happen much more than we think, when you have time to search the Japanese patent office, you discover that much of what you thought was innovative, the Japanese had patented several decades before.
The more I investigate in the past, the more I see that the present has nothing innovative

[husaberg]

“I think there is a world market for maybe five computers.”

Thomas Watson, president of IBM, 1943

“Television won’t be able to hold on to any market it captures after the first six months. People will soon get tired of staring at a plywood box every night.”

Darryl Zanuck, executive at 20th Century Fox, 1946

“Almost all of the many predictions now being made about 1996 hinge on the Internet’s continuing exponential growth. But I predict the Internet will soon go spectacularly supernova and in 1996 catastrophically collapse.”

Robert Metcalfe, founder of 3Com, 1995

“Apple is already dead.”

Nathan Myhrvold, former Microsoft CTO, 1997

[WilDun]

That tends to happen much more than we think, when you have time to search the Japanese patent office, you discover that much of what you thought was innovative, the Japanese had patented several decades before.
The more I investigate in the past, the more I see that the present has nothing innovative

Ceci, - Although the bearing part is essentially true and worth a look at least!, I did mean the idea of having discovered "opposed piston" to be a silly joke (which backfired).

Yes, there are no longer all the "breakthroughs" we used to get in the last century! but there will also be a lot of lapsed patents from that time - which need to be looked through (you have found quite a few already) and probably which could inspire a starting point for other designs!

The evolution of electric vehicles has somehow upset the flow!

[WilDun]

“I think there is a world market for maybe five computers.”

Thomas Watson, president of IBM, 1943

“Television won’t be able to hold on to any market it captures after the first six months. People will soon get tired of staring at a plywood box every night.”

Darryl Zanuck, executive at 20th Century Fox, 1946

“Almost all of the many predictions now being made about 1996 hinge on the Internet’s continuing exponential growth. But I predict the Internet will soon go spectacularly supernova and in 1996 catastrophically collapse.”

Robert Metcalfe, founder of 3Com, 1995

“Apple is already dead.”

Nathan Myhrvold, former Microsoft CTO, 1997

Yep, all true nobody knows what's ahead! (except me!).

(and I have grave doubts about " The Two Stroke" - (The Return Of.) -

but there is still hope! (don't forget the compactness and Power to weight ratio!)
Still a couple of little details to "clean up" etc and it'll make a spectacular return when they all come to their senses!
.

[ceci]

Ceci, - Although the bearing part is essentially true and worth a look at least!, I did mean the idea of having discovered "opposed piston" to be a silly joke (which backfired).

Yes, there are no longer all the "breakthroughs" we used to get in the last century! but there will also be a lot of lapsed patents from that time - which need to be looked through (you have found quite a few already) and probably which could inspire a starting point for other designs!

The evolution of electric vehicles has somehow upset the flow!

I'm sorry for not understanding your humor.
The world of the two stroke engine is very beautiful, that beauty catches you and that leads you to want to know everything about it.
You feel a contradiction when you discover that you were enthusiastic about it and that you currently believed "in evolution projects". These already existed before, and the question is whether these people who present it as "innovative" were already aware of its existence

[ken seeber]

Over here in Western Australia, we have a lot of development going on with renewables, particularly wind and solar, the main application for local usage (particularly in mining) and the potential to export the energy. One in particular is:

https://ffi.com.au/technology/green-ammonia/

As you can see, normally "Ammonia is a colorless highly irritating gas with a sharp suffocating odor. It dissolves easily in water to form ammonium hydroxide solution which can cause irritation and burns. Ammonia gas is easily compressed and forms a clear, colorless liquid under pressure", but the stuff made here is green.

Lots of apparent effort going into using hydrogen and ammonia as a combustible fuel.

Just hope that the huge number of required solar panels can be made here rather than from China where they value add the raw materials from Australia. Also the wind turbines and towers.

[lohring]

It's more than solar panels and wind turbines. Australia is on the cutting edge of the new power generation.
https://en.wikipedia.org/wiki/Hornsdale_Power_Reserve

Lohring Miller

[WilDun]

That does looks like great research! - maybe there still some great breakthroughs still to be made!

Around maybe 30 years ago, there was a burst of energy with research into using Silicon Nitride (basically pressed / sintered silicon powder which was nitrided in the same fashion as steel (done at relatively low temperatures using Ammonia Gas) - this was being promoted as a possible great material for cylinder bores (even totally ceramic engine castings) - seemingly an extremely lightweight, hard and shock resistant ceramic material - anyone here know why that didn't ever actually come to pass?

[Toki]

The main problem with rotary valve head engines is when they use oil to cool and lubricate the valves.
Unlike poppet valves, they introduce oil-wetted, moving surfaces to the combustion chamber, resulting in burnt oil and smoke.
Labyrinth seals work well for 2 stroke crank chambers, but then there are no hot gases to control, and pressures are relatively low.
Tests with un-oiled (eg graphite sealed) rotary valves reportedly did not produce good results - maybe because being carbon, they burnt.
Maybe one day they'll invent some new material that will cope.

[husaberg]

Odd (lab seals) can seal a turbo and a gas turbine, both were developed with a war time rush and unlimited funding.
Lots of gas turbines use lab seals as do some steam turbines
from wiki.

modern high-performance gas turbines use dry gas seals which use spring-loaded rings with an inert gas in between the faces of the rings to provide the seal. This creates even lower friction and provides a liquid-free seal

Labyrinth seals on rotating shafts provide non-contact sealing action by controlling the passage of fluid through a variety of chambers by centrifugal motion.

there is another from of Lab seals that were used on two stroked that used piston rings First time i seen them used was on the DKW threes
i have posted pics before.

STD lab seal convoluted path Yamaha type this on is TZR250


above piston ring types
you will note similar ring seals well grooved for the rings mentioned in the text on the aussie rotary valve i posted a few pages back


Before materials (most developed funny enough for gas turbines ie austenitic steel) caught up with HP development things like sodium filled valves were used to help dissipate the heat. not cool all they do is move heat. From the head to the stem
Nuclear reactors French and i think us have been built with internal sodium used as a heat transfer medium.
“Superphénix,”
(not to be confused with molten salt reactors)

Norton Creighton (i think rather than hele) designed a system that used a vacuum form the exhaust to draw air through the middle of the rotors to cool the Norton rotary
originally it had a system that used its air charge to cool the rotors which is not great for power obviously

With an engine from a scrapped police Interpol and working out of the caretaker’s shed at Norton’s Lichfield base, Crighton’s masterstroke was coming up with what he called the ‘exhaust ejector’ which, similar to two-stroke expansion chamber theory, used the notoriously hot rotary’s exhaust venturi to drag cooling air through the engine’s internals in turn allowing air for the carbs to arrive unrestricted.

The effect almost doubled the rotary’s power output and also made it incredibly loud, although for racing purposes that didn’t really matter…

Norton rotary, Cycle's April 1990 article.

"Unlike most other Wankel rotaries, the Norton engine uses air rather than oil to cool its rotors. This reduces internal friction and makes for a
mechanically simpler engine, at the expense of having to route intake air
along a convoluted path.

"Entering through air filters inside the right and left sides of the fairing,
twin airstreams travel down through the rotor bearings (lubricated by
two-stroke oil), cool the spinning rotors from the inside, then meet in the
engine's middle before being drawn up and out into a plenum chamber. From there, the air enters the two 34mm Mikuni downdraft carbs and is charged into the combustion chambers."

"On the race bike, a simpler, more effective intake system is used:Carburetors pull cool air directly from the atmosphere, while the rotors are cooled by air sucked through the engine and into the exhaust by an air-ejector system (which means the two-stoke oil that lubricates the engine passes through unburned). Those two modifications win an extra 30 horsepower, but aren't practical for road use."

but hey if it was easy to would be done already....
was looking for the air cooling system and found this worth a read
https://www.nortonownersclub.org/history/rotary

[Toki]

Interesting to see the DKW all-metal seals, just like the one in my Goggomobil bubble car (centre seal).
I wouldn't have thought of it as a labyrinth seal though, as it relied on sliding parts rather than no-contact labyrinths.

I didn't know about turbines having lab seals.
I imagine they wouldn't be as simple as the one in my Yamaha YL-1.

[pete376403]

Not sure if this has been posted here yet but anyway. The bike will be on display this weekend in the BSA club show at Upper Hutt
https://www.engrichmotorcycle.nz/

[Flettner]

Willdun, Im just going to run with this for now, my twostroke future, as it were 😁. Finaly found the time and got the bugger off the dyno for a rip around Saturday, angry yet refined is the best way to describe it, vairable rotary disc valve TPI engine, E85 fuel. It goes real well.