Stirlingengineforum.com

Hello all, what do you think of a teacup stirling engine with a
square or rectangular piston and cylinder wall ?
Do you foresee any problems with such a design functioning ?
I look forward to your feedback, Cheers .....
The next round is on me !

Please have a look-see at Jim Larsen's fine works! He has a few rectangular units if I recall correctly...

http://StirlingBuilder.com

Cheers!
-NerdyEE

NerdyEE, Should be no problem if you are either good with the milling machine, or if you have been taught how to use a hand file properly, ie., as an aprentice in a larger (usually government)engineering establishment, or the armed forces engineering branch, as I was in the RNZAF as an engine fitter/mechanic. You still need the same clearances, and if you are any good, a square piston should fit its ??cylinder any way round (what do you call it?). But would you want to. A square displacer, I think the way they have been made is that at one edge a hinge is fitted, and it works like an old fashond bellows, I think that system was used in some of the early LTD motors. Ian S C

What would be the odds of a piston and displacer zone
functioning as ltd in a horizontal position ?
Many thanks , Next rounds on me

I guess with a tea cup engine it doesnt matter so much, but there must be some big disadvantage to a square piston when pressure and heat go up.In every way ,the math the milling, square and straight are easier to do.They didnt have square steam pistons ,no car has a square piston.Iam just curious.All I can think of is when the metal expands, it expands in only two directions with a square,causing pressure points.With a circle the expansion is more or less even.Is this the reason or is it something else?

Well the concept of hand working a perfect circle compared to a square is my concept advantage, and it is somewhat abstract in conventions to what has been done for years.

Many Thanks, the Dog

Bulldog, please dont take what I said as any criticism. Ive just wondered why the simplist and most perfect solution hasnt been used.Engine blocks are square.You could get more cubic inches in. ceramic engines in the future might have square pistons.I think you have a good idea.

Hello and many thanks to everyone,
I am very open to ideas and criticism , hey whats life without input, be it positive or negative, we only aim for the end goal of achievement and everyone learns and gains. We have a great deal of knowledge and hands on experience in this forum, I am new here and ......... the next round is on Me !

Have a great day ....... the Dog

How about a square displacer, ie., hinged as I said before, and a diaphram on the power side. Ian S C

Hello Ian sc
Do you think that the concept would work in a horizontal mode, being able to get the piston to lift horizontally with the difference in gravity might take more work than in a vertical mode, I dont think this has ever been attempted,
what do you think ?

Many Thanks, the Dog

Well I guess that there are no replys it must be able to function,

Cheers ! The Dog

Iam really looking forward to a video of the engine. I hope you can give it a little endurance test and see if square wares more than round.