Stirlingengineforum.com

Derwood The Thermo Lag engine (Lamina flow, not that there is any laminar flow, it's all turbulet!) is not a constant speed engine. From the most recent tests on my engine (only 20cc) it will run from a few hundred rpm at about 40w input to 3150rpm when red hot, off load, as can be seen from the pow...

Fullofhotair

In the arrangement you describe, the lowest heat exchanger will lower the gas temperature as it transfers heat from the flue gases so the next exchanger will see a lower temperature and so on.

GeoffV

Fullofhotair Ceramic coef of expansion is about half that of graphite so it would be impossible to maintain a good seal as the temperature of the heater increases. Which still leaves the problem of attaching and sealing the displacer to the displacer rod through the piston tube. Furthermore as the a...

Fullofhotair 10 out of 10 for lateral thinking but sadly it will not work and even if it were modified it could not be made. As drawn, the air on each side of the 'firewall' remains in the hot volume at all times, for it to work the air must be displaced each 180deg of rotation to the cooled volume....

Derwood Thanks for the video, if a picture is worth a thousand words then a video is worth several thousand. I spent much of the week trying to analyse the effect of the choke on the TL cycle and thought my preliminary results may help you decide on your next move. The main problem encountered was c...

Derwood Thanks for your progress report. Also cooling the cylinder does seem to increase power but cooling the choke seems to decrease power I note with interest that your findings regarding cooling reflect my experiences and are very much inline with the article from the Univeristy of Gent. Keep up...

Hopper Nearly 200 years have passed since Robert Stirling applied for a patent for his regenerator yet the Hot Air engine probably dates back some what earlier to Caley, one would have thought that after all this time everything there is to know would be known about these engines. However there are ...

Zhivko I agree with your comments regarding the cooler, at the moment, but with improvements to the heater and a concentric displacer to aid the heat transfer the next problem is likely to be the lack of water cooling. I understand that Peter realised a significant power increase (170 to 260w) on on...

Zhivko From what I have seen so far of the #14 engine by Peter Lynn, my best advice to you would be to recommend you delay spending money on fancy heat exchangers and develop the engine you already have. From your video, I suspect your engine is suffering from too much friction and would benefit fro...

Gentlemen Having been in regular contact with Peter over the last few weeks, I have no doubts in my mind that he is achieving nearly 500watts continious power from this engine, which would be sufficient to propel this beautiful boat at the claimed speeds. If you wish to question anything, it should ...

Zhivko This thread started with a desire to build a 1Kw stirling engine, the latest drawing is of a slotted cylinder with a heat transfer capability of nearer 160Kw, even at just 10% internal thermal efficiency this would equate to a power output sixteen times more than your original plans. Not that...

Zhivko From your calculations it seems you have selected slots just 2.38mm deep, why, they can be 10mm deep or 20mm deep? You also seem to have used a value for H of 20 w/m2/k, probably about right for large bore tubes but 0.4mm slots will transfer nearer 160 w/m2/k. Peter Lynn points out the limiti...

Bumpkin

I take it that's a NO to fairey lights then, pity.

GeoffV

Zhivko Tubular heat exchangers are very good at adding surface area, but by comparison to slotted heat exchangers (being inside and adjacent to the cylinder walls) they add a lot of dead volume, even worse they restrict the pass area. The Philips 1002ca produces 500w at the crankshaft from 61cc work...

Zhivko Before you start cutting and changing the engine I would respectfully suggest you 'fix the Bloody leak' and see where you've got to so far and never mind worrying about the engine 'freewheeling to destruction', trying to pump 9ltrs through a 3.5mm wide gap will stop it overrevving for sure. I...