Need some advice!

Discussion on Stirling or "hot air" engines (all types)
Post Reply
Canuck
Posts: 5
Joined: Fri Oct 12, 2007 3:47 pm
Location: Canada!

Need some advice!

Post by Canuck » Wed Oct 17, 2007 10:09 am

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
Image[/img]

boydhouse
Site Admin
Posts: 87
Joined: Mon Jan 30, 2006 9:04 pm
Location: Concord California
Contact:

Post by boydhouse » Thu Oct 18, 2007 5:54 am

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

Canuck
Posts: 5
Joined: Fri Oct 12, 2007 3:47 pm
Location: Canada!

Post by Canuck » Thu Oct 18, 2007 2:15 pm

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

SScandizzo
Posts: 66
Joined: Tue May 16, 2006 5:06 pm
Location: California

Post by SScandizzo » Sun Oct 21, 2007 11:30 pm

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

Canuck
Posts: 5
Joined: Fri Oct 12, 2007 3:47 pm
Location: Canada!

Post by Canuck » Thu Oct 25, 2007 9:30 am

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

alpha stirling
Posts: 35
Joined: Sun Apr 29, 2007 9:24 am

Post by alpha stirling » Thu Oct 25, 2007 11:29 am

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
They told me one cannot build a jet engine in garage conditions. I proved them wrong and I was only 16 :P

Don't let people's sayings discourage your creativity!

Canuck
Posts: 5
Joined: Fri Oct 12, 2007 3:47 pm
Location: Canada!

Post by Canuck » Thu Oct 25, 2007 5:40 pm

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

SScandizzo
Posts: 66
Joined: Tue May 16, 2006 5:06 pm
Location: California

Post by SScandizzo » Fri Oct 26, 2007 12:33 am

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

Post Reply