DISPASER QUESTION

Discussion on Stirling or "hot air" engines (all types)
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antidartan
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DISPASER QUESTION

Post by antidartan » Mon Sep 17, 2007 11:17 am

i am trying to build a tin can sterling engin. I have the preasure vessil and displacer built according to the plans. The displacer can travel high enough to go past the hole going to the power piston. Is that a problem or do i just make the crank shaft in such a way that it limits the throw of the dispacer? :-?

Thanks
Antidartan

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SScandizzo
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Post by SScandizzo » Mon Sep 17, 2007 5:55 pm

Hi Antidartan,

Welcome to the world of Stirling engines!

The displacer should travel the entire length of the displacer cylinder so that at either end of the cycle it is either almost touching the top or bottom of the cylinder. The location of the hole to the power cylinder is of little consequence in this design.

-Stefan

antidartan
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Location: ROCHESTER,ny

displacer

Post by antidartan » Tue Sep 18, 2007 4:52 am

Thaks for the info. Exuse my spelling of displacer, wine does that to me:)
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antidartan
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Post by antidartan » Wed Oct 03, 2007 3:21 pm

On all the modles I have seen, the displacer is fairly thick. Is there a problem with the displacer being a thin piece of metal?
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boydhouse
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Post by boydhouse » Tue Oct 09, 2007 5:49 am

On a tin can engine........a thin piece of metal does not "displace" a lot of air. The job of the displacer is not that of a piston like in an engine, but to displace air from one side to the other. It needs volume to do that.

Maybe I should think about changing the name of the "displacer piston" to just "displacer"?? and leave the name "power piston" as is??

DB

SScandizzo
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Post by SScandizzo » Tue Oct 09, 2007 1:08 pm

Hi Antidartan,

The displacer moves air back and forth between the hot and cold ends of the displacer cylinder. The material it is made from should be as light as possible for two reasons: first, thinner material conducts heat less than thicker material and second, a lighter displacer requires less work to move it back and forth.

The VOLUME of the displacer is a different story. It should be a wide as the plans show because it must DISPLACE a large volume of air when it moves.

Hope this helps!

-Stefan

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