Stirling 'first run'

[Chriske]

Hi,

http://gti-duffel.be/4B/StirlingCD/Stirling-CD01.mpg



This is what pupils from our school (GTI-Duffel - Belgium) made.
It took about 5 pupils on a 2 hours/week basis to finish it in almost 4 months.

Purpose is to have this engine mounted on a base to run on a track gauge 1. Most parts of that base already done.

Chris

[Ian S C]

Chris, I can see the hot end, and the burner, and your tools, could you post the rest of it, If the rest is as good as what I can see, it will be worth another photo. Ian S C

[Chriske]

Ian,

Don't understand what happened, maybe there is a problem with the resising of that image. I posted an image to large... sorry...!
But there is also a link showing the engine in motion.

Chris

[Ian S C]

Chriske, no problem, its was just me not knowing how things work. Click on the top line above the photo, and it goes to full size. Nice motor, give the kids top marks. Ian S C

[Chriske]

The kids (second grade) made all the parts and together we did the polishing and assembling.
Some of them came even after hours to help me out. Great kids..!

[Ian S C]

Chriske, a couple of ideas.(1) If you could rig a little fan driven by the motor, and placed adjacent the power cylinder, this might give a wee bit longer running between burnt fingers. (2) An experiment worth trying, put a small pully on the motor, get an electric motor with a pully, join the two together with a rubber band and run the motor in its normal direction, after a few minutes feel the hot end (or put a thermometer on it), you should see condensation inside, and perhaps a light frost on the outside, This demonstrates one of the most important uses of the Stirling engine. The cold end will get quite warm, its a heat pump. Got other ideas, but I'll leave them out for now. I think from the photo that the pillar holding the beam can be slid along the motor, you have proberbly tried adjusting the possition, this alters the phase angle, there by giving possible power adjustment. Ian S C

[Chriske]

This is how I cut the glass cilinder :

[Chriske]

Hi there,

This engine got faster after it has 'ran in' for an hour or two.
http://gti-duffel.be/4B/StirlingCD/Stirling-CD02.mpg
Compare the speed with the first link higher up in this thread. I did not expect it would run this fast at all.
Still, it needs to be tuned some more. It has not been balanced yet to stop the vibration of the upper part.
Maybe I'll drill he large hole in the flywheel or just add some weight to remove these vibrations.

[Ian S C]

Chriske, As for the balance, you proberbly don't have to worry too much, my little beam motor vibrates like man as it speeds up, once it is at it' running speed it settles down and runs smoothly, then as it cools, it starts vibrating again. No single cylinder motor is fully balanced, and a stirling engine is not much different. What I would do is take the vertical con rods, and either make them much narrower, or drill a row of holes , say 5 or 6 mm dia, about 10 mm apart, this to loose a bit of weight, can't see it , but I imagine the con rod for the displacer is similar, so it could all so be treated the same. The beam could be lightened as well. Lightening the moving parts reduces the violence of the vibration.
On my motor the con rods are 3 mm square, but when, or if I take it apart I will thin them down a bit, perhaps 3 mm X 1 .5 mm thick. The beam cosists of two bits of 1 mm X 8 mm, held apart by 3 mm spacers, that way the con rods are attached in double shear. The con rods, and beam are made of aluminium, with brass bushes in the moving bearings. the big end bearings and main bearings are ball races. Ian S C

[Chriske]

maidenrun.....!

http://gti-duffel.be/4B/StirlingCD/Stirling-CD03.mpg

a little bit extra power is needed to force itself easier and faster through the curved parts of the track.
but beside this minor 'problem' we're very happy with the result.

While running it sounds rather load but that's because it was driven in a very large hall.

Chris

[Ian S C]

Unfortunately, I can't load quicktime, but its good your little motor is on the rails and going. Ithink the rail people get round the problem of tight running on curves by widening the track a fraction, not enough for the wheels to fall through, just enough to give the flanges clearance, you might be able to narrow the wheel gauge by a fraction of a mm. Ian S C

[Ante]

Very nice machine.

Salute!

[Chriske]

Unfortunately, I can't load quicktime, but its good your little motor is on the rails and going. Ithink the rail people get round the problem of tight running on curves by widening the track a fraction, not enough for the wheels to fall through, just enough to give the flanges clearance, you might be able to narrow the wheel gauge by a fraction of a mm. Ian S C

Ian,
No quicktime needed as it is a mpg file...
I thought about it, narrowing the wheel gauge and I did. As a matter of fact I can move the complete unit about 2mm sideways between its tracks.
Better would be narrowing the distance between the two axis, but that is to late now as our open door is in sight...

I'll tell my pupils Ante, thanks btw. Although I must admid, without the help of a few good men I think it would have been hard to end this project with succes. Credits goes to Dirk and Wim and a few others.

Whe had lots of fun making these Stirlings.
Planning to make some more next schoolyear.
I think I'm hooked for life...! Thanks for this to guys...!

Chris

[vile_fly]

Wow....super pretty engine and it works well, too! Wish I could make pretty ones like that. Ugly and functional is usually what my projects look like.
Introducing the fly seal of approval.

[Chriske]

Showtime during open door is coming our way...!
My pupils are very proud with these engines. They worked very hard to accomplish this result.

http://gti-duffel.be/4B/StirlingCD/Stirling-CD04.mpg

In the movie the engines do run but were not completely finished, but this very moment they are. Some minor problems had te be solved. The most urgent problem was its speed. These engines need to be lubricated to have it run at very high speed. If lubrication is not applied speed wil drop to about 1/3 of it's max. speed. The parts that needs a drop of oil from time to time is the displacer-axis.