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Hi hows if going, new to the forum and fairly new to stirling engines.
Im trying to design a displacer type, stirling engine and want to know if this plan would work. any suggestions/advice are welcome!
Im using copper wire for the crank and connecting rods, to cardboard disc's as a displacer, soup can as a pressure vessel (I think its called) and a cut balloon as the power piston. the top of the can will be sealed by a cardboard disc ( if it'll work).


Thanks in advance,

Canuck
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Hello Canuck,

Sure looks like a design that has been done before. Check out this website and see what you think.

http://www.physics.sfasu.edu/astro/cour ... rling.html

DB

Awesome thanks alot! Yea it is pretty similar.
a quick question, the displacer crank is suppose to be bend 90 deg. to the power piston crank, right? also when the displacer is at its bottom stroke, where should the power piston be? lol im new to this stuff and this is my first stirling.

Thanks again,

Canuck

Hi Canuck!

Welcome to the forum. The two cranks should be 90 degrees (or 1/4 rotation) offset from each other as you suggested. If you use a balloon as your power diaphragm, it will be easiest if you set it first, when cold, at the 6 o'clock position. Then adjust the crank length for the displacer so that it is midway between the top and bottom of the chamber and the crank is at either the 9 o'clock or 3 o'clock position (the only difference it makes is whether the engine spins clockwise or counter clockwise). I've made this particular engine and it ran the very first time I tried it. Follow the directions carefully, and avoid using cardboard for your displacer as it may char with too much heat. =)

Let us know how it turns out!

-Stefan

Well i finally put it all together, and!!!...it didnt work:( lol doesnt matter, im going to tear it apart and see whats up. I think the balloon power piston, isnt being pushed down enough. Ill post a pic of it a little later, been busy with homework latly:P What would you recommend for a diaplacer, other then cardboard?
Thanks for the replies,

Canuck

Hmm... What kind of cardboard did you use? If you just laminated (stacked) crinkled cardboard, then your displacer might be too porous. Try wrapping it in duct tape or similar to prevent air going in/out. This'll usually work

yea i used the crinked kind, and ill try the duct tape idea. Next Monday ill tear into it.

I'd suggest using aluminum from soda cans as your displacer. Very light and easy to work with. Use something like JB Weld as the glue and it should be airtight. Take a closer look at the link DB posted. If you follow that design correctly, you should have no worries.

-Stefan