Displacement ratio for double acting 4 cylinder stirling

Discussion on Stirling or "hot air" engines (all types)
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danalinscott
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Joined: Mon Nov 27, 2017 10:25 am

Displacement ratio for double acting 4 cylinder stirling

Post by danalinscott »

I am designing a 4 cylinder double acting Stirling engine and double checking the info regarding displacer and power piston displacement ratio as 1:1.

Is this correct?
Tom Booth
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Re: Displacement ratio for double acting 4 cylinder stirling

Post by Tom Booth »

danalinscott wrote: Fri Jan 17, 2020 12:15 pm I am designing a 4 cylinder double acting Stirling engine and double checking the info regarding displacer and power piston displacement ratio as 1:1.

Is this correct?
I think that would vary depending on your operating temperature. The more a volume of gas is heated the more it can expand.

Someone recommended to me a long time ago, disconnect the power piston from the connecting rod and operate the displacer manually. The power piston will move without mechanical interference and indicate the extent of the throw.

I think this page addresses the issue, for Stirling engines in general, though I can't say that I understand it.

http://www.solarheatengines.com/2012/02 ... g-engines/
danalinscott
Posts: 26
Joined: Mon Nov 27, 2017 10:25 am

Re: Displacement ratio for double acting 4 cylinder stirling

Post by danalinscott »

Thanks for the reply.
The link you provided appears to be for all but alpha type engines.
The 4 cylinder double acting stirling engine is an alpha type.
Tom Booth
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Location: Fort Plain New York USA
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Re: Displacement ratio for double acting 4 cylinder stirling

Post by Tom Booth »

I see at least one engine of that description on YouTube. It is an old video, but the author seems willing to answer questions and share his experience and specifications. There is some information in the comments.

https://youtu.be/iRjKnzpZqIg
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