Solar-powered Stirling engine design details
December 24, 2011 – 2:48 pmI’ve put together a video of the latest version of the LT-2 Stirling engine. Because this low-temperature engine has minimal output power I sometimes consider it more of an artwork than an engine. I often refer to it as the sculpture engine.
What this engine lacks in power it makes up for in reliable operation. I have more than 200 hours of operation under solar power and at least 100 more hours running under incandescent light. It shows no sign of wearing out.
I’m now trying to decide if I want to work on the next step which would be a new design for an all-weather version that could be permanently mounted outside. Whether I build that next design or not, I thought I would make the details of this prototype engine available to other Stirling engine enthusiasts.
I’ve put together a very detailed discussion of the parts and what is important in the design and construction. There are so many photos I’ve split the information among 4 different pages. I tell you not only what I did but what I would recommend to make it better (that part is for my own benefit too). Here are the links:
Part 1
Part 2
Part 3
Part 4
I hope you find this useful.
The only thing I haven’t covered in detail is the engine controller electronics and software. I may put that up in the future if I get requests. I’m assuming most people will just be interested in the engine, not the starter and electronics.
2 Responses to “Solar-powered Stirling engine design details”
Hi Doug
Great detailed information. Good to hear you’ve exceeded your own design goal – that shot in the video showing the length of your own shadow really brings home how low the sun is at this point.
Regarding balancing – and I realise how time-consuming creating all this is – could you make how you go about this a topic in a future post? I’ve an idea (hopefully wrong) that it’s not as simple as it sounds…
Thanks very much
Alan
By Alan on Dec 26, 2011
The balancing I use on this engine is just simple static balancing. When the crank pin for the displacer is horizontal (3 or 9 on a clock face), I weight the flywheel (also at the 3 or 9 position) so it balances in that position. Then I turn the crankshaft 90 degrees so the power piston crank pin is horizontal and add weight to balance it at that position. All this is done without compression. Now the flywheel can be turned to any position and it should stay there. I suppose there are inaccuracies caused by the connecting rod length but they are minor. Above 100 rpm or so you don’t even need to do this type of balancing.
By admin on Dec 26, 2011