Quick description for rebuilding the thermoacoustic prototype:

My test tube has DO 19.75mm DI 17,6mm and a length of 136mm.

You have to adjust the cooler connections accordingly.

The cooling fins are not in the drawing, as they are far from optimal in my test engine and must be improved.

Its possible to print them in high temperatur material and insert wires with adhesive for good cooling, there you have to experiment according to your possibilities.

I have sealed with O-rings, but it also works with adhesive or Teflon. 

The heater is made on the milling machine but can also bend from stripped power cable which can be spiral bend or else.

Copper oxidises very strongly in the heater, perhaps a different material would be better?

The regenrator is stainless steel mesh 40 or similar lenght 25mm for first tests stainless steel wool can be used

The connections to the inertance,compliance and power extraction branch can be 3d printed if the prints are made airtight with epoxy/paint/dichtol etc.

I used copper plumbing parts which can be easy soldered with a cheap torch and a soldering set for plumbing or just glued together.

I got stable testruns with tube diamereters of 25 and 20 mm inner diameter and length of 250 and 350 mm look at the photos of the engine and experiment with the lenght, its not too critical. 

Reinforced pressure hoses tubes are much better than plain PVC tubes!

I turned the power cylinder from cast iron and the piston is IGUS W300 tribological plastics.

Both parts can be printed, look for a good gliding filament or use IGUS filaments which are not too expensive but I made good experiences with them.

The piston has to slide with very low friction and must be ground in, which is not that difficult.

The engine will surely not run at your first tests, be patient and make one change at a time, note it and try again.

Good luck and plz report and show photos, I will show your results in the next video.

My email is on my channel page!

Sorry for the provisional text, I am very busy at the moment and just want to give this description fast!

If any important things are missing or for any questions or wishes plz write in the comments on youtube, I will answer!



