Possibility of single stroke engine.

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Looking into for the future of building my own plan. I like the common engines but I just want something unique per say. Would a single stroke engine be possible in the case that fuel and air would be pre mixed and injected just before top dead center then ignited and burned for the down stroke/combustion. Before starting what would be the new compression stroke a valve would open pulling a strong enough vacuum to pull the exhaust and close letting the piston rise to another spot before top dead and open a valve with the fuel and air mixture already mixed and under pressure for the combustion to be pushed into the cylinder to be burned next?
 

gtae07

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Where's the pre-compressed air getting compressed?


The place for brand-new engine concepts is the test bench and the lab, not a flying airplane. You'd be better off using an existing engine, especially on a unique airplane.
 

akwrencher

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The level of complexity to make something like that work would be an order of magnitude more complicated than existing engines. Plus, you really can't fit more than one combustion event per revolution. It's just not practical (possible?). There are plenty of unique engine solutions just in the conversion realm and they are plenty challenging enough of a project for even the "advanced" guys to get right.
 
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Where's the pre-compressed air getting compressed?


The place for brand-new engine concepts is the test bench and the lab, not a flying airplane. You'd be better off using an existing engine, especially on a unique airplane.
I was thinking an electric driven compressor when the engines starting then let it be engine driven or geared up from the engine.
 

Attachments

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Piston down stroke, piston rises (up stoke) moves up, sounds like a two stroke to me.
I have true single stroke in my closet, a Springfield model 1903 caliber 30, it has no return stroke what so ever.
Well it would be if your piston was at that top level. Fuel and air would be injected under pressure (same as if the piston compressed it) infighter that’s my Down stroke- at the very bottom of the stroke just before it would return up a valve opens and pulls via a vacuum the exhaust then leaves the piston chamber and as the piston rises just before it is at its peak fuel and air is pushed in then infighter and it repeated. One stroke per revolution via one intake and one exhaust.
 

Riggerrob

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The inventor is going to need to devote much time to developing intake compressors and exhaust suction pumps. The external plumbing will probably exceed the weight and complexity of the combustion chamber.

The only way I can see making this a true 'single-stroke" is installing a floating piston that fires when moving in both directions. Install intake and exhaust valves at opposite ends of the cylinder.
The next challenge is figuring out how to attach a single floating piston to a crankshaft??????
The nearest I have seen - so far - is a Scotch Yoke connecting a pair of pistons. ?????????

An intriguing concept ......
Wanders off scratching head .........
 

Swampyankee

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bmcj

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I’m with Jerry and AK, the new design described by the OP is still a 2-stroke engine. Hephaestus hit the nail on the head, this sounds like a reed-valve engine used in model airplanes.

The only real difference between a 2-stroke and the OP’s idea is the pre-compression of the air and fuel before it is injected into the combustion chamber, which means extra complexity as well as compressing an explosive mixture in part of the engine NOT designed for explosive expansion.
 

Aerowerx

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(Somehow the quote from pictsidhe didn't get quoted.)

Ah, shucks!

You stole my answer!

As I recall, they were rather finicky little beasties to get working properly. And tended to make a mess with all the unburnt castor oil and alcohol flying everywhere when that port opened. Not very efficient either, I would guess.


Hmmm. Wonder what a 40 HP one would sound like. Freight train in your living room???
 
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