twostroke swing free piston engine

[shiman6d]

i see this as fairly plausible, except for there is nothing spinning to drive anything

[killytbe6]

What if you put another one on top, so as to make an '8'?

[io9487]

@killytbe6

that would be better because of the force free center. But still more comlicated. If you're still interested I can inform you about the 4-stroke version when it's patented ;)

[killytbe6]

somebody build this already

[io9487]

@killytbe6

who? Do u have a vid?

[killytbe6]

@io9487 no as in 'somebody hurry up and build this already!'

[io9487]

@ioanniosif

Thanks for your comment. The control of this engine is not easy. Google "Free Piston Engine" to learn how this works. The Swing Free Piston Engine is just a special form which can be EASILY BALANCED by adding a counter rotating generator rotor.

[ioanniosif]

Turn to the right, turn to the left, why do you think it works

[badass96ford1]

@tthhnnee im assuming it won't hit the heads just due to the compression but if there is something wrong with one cylinder there's gonna be issues

[tthhnnee]

I like the Idea, but how do you manage to avoid piston hitting top cylinder wall? for instance in case of a missfire of one of the pistons?

[io9487]

many small stationary single cylinder engines are unbealanced ever since. That doesn't harm their usage.

[UBConquered]

How the hell is that supposed to work? Its unbalanced!

[iLoveEatingPie]

It appears that it would vibrate like hell.

[JaxxBat]

There are over a dozen of these rotor/stator 2 strokes patented and they all do the same thing wrong..

[io9487]

@JaxxBat

and this is what?

[robthatguyx]

@io9487 there not balanced

[io9487]

It directly drives an alternator

[UNKLDAVE]

What would this type engine drive? with out adding a rod assembly and a flywheel, I just dont see an application? And adding all that stuff makes the design kinda moot? Dont it?

[JaxxBat]

@UNKLDAVE , No. Converting to rotation is done in a few ways..

[UNKLDAVE]

@JaxxBat Tell me? I am interested!

[io9487]

if one side begins to misfire, the engine will stop, since the compressed gas will expand unburned, the generator (or the used load) will eat the energy and then it stops. Misfiring just shouldn't happen. If it does, the engine has to be restarted.

Why should the piston strike the head? The charge must be compressed infinetly (assuming no leakages) for that, but thats impossible!

[tsbrownie]

Interesting, but if one side begins to misfire, what keeps that piston from striking the head? It might also happen on rapid acceleration where one side will receive a higher fuel charge relative to the other.

[io9487]

I found sth. very interesting a papar about a very similar engine:

"Performance analysis of a 2-stroke micro free-piston swing engine"

written by Zhang Shimin, Guo Zhiping and Wang Jinsong

you will find it using google

[io9487]

Uniflow scavening is also possible: Note the second inlet/ exhaust at the center of the shaft.

[io9487]

Of course, a twostroke stays a twostroke. But short cut scavenging issue is solved in modern twostrokes for example by direct injection (search for "e-tek injection" on the web), there are other ways to solve this. Very common in snowmobile and boat engines.

Much more interesting is challange of inner lubrication, using oil/fuel mixture, which leads to HC emissions. That can only be prevented by using air "lubrication" for the piston rings. This is what the design aims on.

[5m1th3rz]

Surely with this you have the same problem a traditional two stroke engine has, in that the inefficient and unclean nature in which it burns fuel, mixing the burned fuel exhaust with the fresh fuel and air mixure..?

[TripleXReborn]

this is genius