Stirling engines

When I first heard of the Stirling engine, and understood its principle, I just had to build one myself. Meanwhile, this has grown into a timeconsuming hobby, but it is a tremendous feeling when after many hours of calculating, designing and constructing, the engine actually runs.

My latest engine is an Alpha type Stirling engine: Version 5a: Alpha type.
240 rpm at a temperature difference of 150 degrees celsius.

This is the result after months of tinkering to reduce mechanical losses. I did not yet measure the output power or the efficiency. There are some improvements planned, and after I will list both. Anyway, I am extremely pleased that I got it to run.

My second attempt was to make a version more powerful: Version 4c: Gamma type.
120 rpm at a temperature difference of 80 degrees celsius.

I tested the mechanical power of this machine by lifting a bottle of water. Changing the amount of water, and recording the lift speed, I calculated the mechanical output power to be about 0.6 W. Not so much yet, but the fact that real work is done is encouraging to build a stronger and more efficient version.

This is my first working Stirling engine: Version 3b: Gamma type without regenerator.
60 rpm at a temperature difference of 80 degrees celsius.

After having added a regenerator, the engine runs at 120 rpm at the same temperature difference. I did not try to measure the mechanical output power: it is enough to keep the engine running, but no more.