Piston stroke

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si_sol
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Joined: Mon Jun 16, 2008 1:10 am
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Piston stroke

Post by si_sol »

Hello,
I'm new to Stirling engine and whould like to know what is the best
practice in determining the stroke size. To my knowledge, longer
stroke size mean lower RPM, so the requirement for sealing will be
lower than higher RPM does. FYI, I'm living in a third world country
and finding a good quality sealing is almost impposible here. What is
the side effect of having longer stroke compared with shorter one ?.


stan.hornbaker
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Response to Piston stroke

Post by stan.hornbaker »

Stroke length of either or both pistons is the least of your problems if you cannot seal the Stirling engine against leakage of the contained gas.

There are several sources of design information for Stirling engines.

Dr. Izz at: http://www.ent.ohiou.edu/~thermo/

A. J. Organ at: http://web.me.com/allan.j.o/The_Hot-Air ... lcome.html
si_sol
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Response to Piston stroke

Post by si_sol »

Thanks for your answer. It seem that there no other option except find a good sealing. But again, finding sealing material that withstand slow linear speed (from a slower rpm) is easier here than trying to find exotic material that withstand higher linear speed.

I've tried to follow the url in your previous post, especially this one : http://www.ent.ohiou.edu/~thermo/Intro/ ... ter3b.html .
Since I'm new to Stirling, can you give me a clue on what part of the design that should be optimized ?. Based on the equation from those url, Work = Const x ln(V2/V1), and it seem that it's a function of compression volume and expansion volume. Compression volume depend on the temperature so I can't find a clue on the sizing aspect of the displacer, piston, stroke, etc.






stan.hornbaker
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Response to Piston stroke

Post by stan.hornbaker »

The links are to educational material on Stirling engines. It appears to me that you are attempting a project with little or no preparation as to the design of a Stirling engine. Designing a Stirling engine from scratch is a formidable job for anyone who has been through Dr. Izz]s course in his classes at Ohio Univ.

Why a Stirling engine? What will you do with it?
si_sol
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Joined: Mon Jun 16, 2008 1:10 am
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Response to Piston stroke

Post by si_sol »

I intent to use it in solar application. Here in my place, the sun shine almost every day, and I think solar Stirling is the right choice.
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