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new displacer

making progress, I still have to fabricate new linkage, the new configuration should be air tight

making progress, I still have to fabricate new linkage, the new configuration should be air tight

[youtube]https://youtu.be/be8xuXqwBaU[/youtube]

Still not working, I am making improvements, suggestions welcome.

Go back and read my entries of 2/3rd July please.
Ian S C

Hi, thanks. I will start searching for more sizable materials. I have been trying to fabricate with off the self parts.

To a certain extent you can get by with bits off the self, and out of the scrap bin, but there comes a time when you actually have to make things, this can involve machining on a lathe, welding, brazing.
Ian S C

Hi, nice work. Do you any engines that are larger? I need about 1/3 HP output.

That one has a bore of 3/8" and stroke of 1/2" for the power piston, power unmeasured. Built of bits found around the workshop. My largest engine could on a good day make about 10 Watts, it has a bore of 2 1/4", and a power stroke of 1 1/4". I don't have the equipment to build much bigger, or a fat enough wallet. Ian S C

Hi, thanks for the info. Is that a 10 watt electrical load? Are you using a MPPT circuit? I look for ward toward your results on the new project. Thanks again.

The power was tested with a brake, and that's the mechanical power at the crankshaft, with a generator on that motor, on another day I got 8 Watt electrical

project update

[youtube]https://youtu.be/1iAG6NwaTXY[/youtube]

Had a look at your video(can't get it on my home computer), (1) I don't understand your hot cap and displacer set up, the displacer appears to be a large diameter, and fairly short. I could not see if the displacer cylinder is sealed. Why is there steel wool around the outside of the hot cap? The stroke of the displacer compared to the power piston seems excessive. The correct swept volume ratio between the two cylinders should be approximately 1.5 : 1. The displacer should be three times it's diameter long, this gives a reasonable distance between the hot and cold ends of the chamber.
Could you post a sketch of what you have built so I can see what you have.
Ian S C

Hi, thanks for the help and the info for optimal dimensions. I will post a drawing when I get it working. I did seal the the displacer. I am working on reducing the friction and I am just experimenting with what I have on hand at this time until I find better sized materials. Thanks again. I should be testing again in a few days.

[youtube]https://youtu.be/MsGukccOABw[/youtube]

Results from last modifications. I am adding a water jacket, increasing the size of the displacer, and changing the power diaphragm. It still needs more suction and less friction.