Double Action Stirling

[Cartech]

I know a Stirling is basically a "one stroke" engine to start with but I've been thinking about building a Stirling with two displacer chambers connected to one power piston at each end. My thoughts would be more power but the more I think about it, I'm loosing the atmosphere stroke and merely replacing it with the expansion stoke of the second chamber? Does anyone think there would be anything gained with this arrangement? I have solved the sealing of the crank and connecting rod so my question isn't how it can be done, just is it worth trying?

[atwooddon]

I know a Stirling is basically a "one stroke" engine to start with but I've been thinking about building a Stirling with two displacer chambers connected to one power piston at each end. My thoughts would be more power but the more I think about it, I'm loosing the atmosphere stroke and merely replacing it with the expansion stoke of the second chamber? Does anyone think there would be anything gained with this arrangement? I have solved the sealing of the crank and connecting rod so my question isn't how it can be done, just is it worth trying?

Do you mean like this one?

www.youtube.com/watch?v=m-qj6V8JMOY

[Cartech]

That's an interesting engine but doesn't look very useful?

My design will have two displacers and one power cylinder mounted between them and each end of the power cylinder will be ported to a displacer. The displacers will run opposite hot/cold cycles from each other and that way as one is drawing the piston in, the other is pushing it out. I have figured out the mechanical issues to make this engine but I'm still uncertain if there will be any benefit to it's design.

[Orrin]

My Web site features some pictures of double-acting hot air engines. Here is one link:

http://www.oldengine.org/members/orrin/Pic_Ctn2.htm

...and another:

http://www.oldengine.org/members/orrin/Pic_Bet2.htm

Regards,

Orrin

[Cartech]

Orrin,

Thanks for the links, these are the first I've seen of "real" double action Stirlings. I'm currently drawing one up and gathering materials for a model. (much smaller than the one's in your links!) I'm still going for LTD and may try to have it run a small vehicle from the heat of road pavement if output is enough. -Cartech

[Henrik]

Pls share with us where you have found your sealings. Im working on similar project. 2 displacers but only 1 power cylinder for both. Bore 110mm / Stroke 100m / pressure 15 bar.

[Cartech]

Henrik,

I'm using an "Airpel" double action air actuator from Airpot Corp. Not big enough for what your working with and I'm not sure how big they even make them but it is very smooth and well sealed. I have most of my materials but I'm too busy to work on it for a while. You might e-mail the guy from the links posted above and ask what that guy is using for his large model double action cylinder. Good luck.