Stirlingengineforum.com

Hello Mac. Your concept sounds very much like the solar project at Tamera. Their engine is a large roll-sock type Beta, suitable for mid to low temp differences. They used oil for thermal storage. I don't know if they're still working on the design. https://www.youtube.com/watch?v=SMMELH7CSNE Bumpkin

I know this is an old thread but here's another recipe that makes me wonder just how far we can take easy home cookery towards producing useful Stirling components:
https://www.youtube.com/watch?v=aqR4_UoBIzY
Bumpkin

I've been posting a bit and lurking a lot for a few years and I want you to know how I respect the the time you put in here. (Including cleaning up idiot adverts and such) A certain kind of mindset (weirdness?) brings us here and it's a blessing to have a community.

Bumpkin

Looks like it's been worked out, but if we would say SWEPT volume for the ratio of displacer to power, it might save some confusion.

Bumpkin

Hi Oscarmike. Here's a link to something about the math stuff. The relevant stuff is towards the top.

http://www.spragueriver.com/index.php/bumpkin-tech

Bumpkin

Hi playludesc Development of these engines is more important to me than the modeling, so know I mean this respectfully. You can always copy other engines, but for unique circumstances and applications you should learn the basic science behind the ratios. You could Google the Ideal gas law or Boyle's...

Hey Ian, I always wondered how a prony brake could be consistent enough to get a good reading. Now I see the springs and it's clear. Thanks. Alfista, I watched the video. I would think it might be easier to test your engine's power by finding the biggest load (light bulbs?) it will run up to voltage...

The trouble, as I see it, with small scale wood gasification is it tends to take a lot more tending than just a basic wood stove. Also if it's done inside a living space there's always some degree of danger from carbon monoxide - stuff happens. There are off-grid folks who use wood-gas to run a more...

Nearly 40 years off-grid here myself, and a big Stirling fan, but it's hard to compete with modern P.V. system prices, even including batteries wires controllers and inverters. A solar Stirling combination with a VAWT is intriguing. The big problem with Stirling rotary displacers is that they move a...

I like your crankshaft design. It always seems funny when people turn the crank back to the main center before swinging it back out 90 degrees, even without the purpose of providing another main bearing. That said; is there a key or something to register the clamping of the second throw for accurate...

I'm not a fan of Alphas except for high temp versions, and even then they generally use heat sources that might be better and more efficiently spent elsewhere. But that said; you can lower the peak volume ratio to where it works with lower temps, with variable volume. The weight of a few inches of w...

Aviator, I forgot to mention another problem with a pressure imbalance above and below the piston. (beyond the normal power pulses) There is a greatly increased rod and main bearing load. I bumped into that while trying to think up a pressurized diaphragm type engine. A set of two opposed and linked...

Hi Pete. Neat that you saw the Jim Dandy six operating. 15 or 20 minute feeding intervals wouldn't be too bad if you were right there working in the shop anyway. Burning home-made fuel beats buying pellets any day. Aviator, you are probably a better machinist than me, but I'd still bet an open-crank...

"Looking to run at 15bar fairly quickly but then maybe more." - You probably already know, but remember not to mix air and oil at high pressures/temperatures. From wikipedia - "At high temperatures and pressures, the oxygen in air-pressurized crankcases, or in the working gas of hot a...

Back to the thread premise; I pretty much agree with this paper:
http://file.scirp.org/pdf/ENG_2015121717392471.pdf
Bumpkin