This is a working model of a steam engine that runs on air.

The input port is on the top and the exhaust ports are on either side.

Airflow inside the engine when the piston is expanding (rendered using mecabricks)...

... and when it's retracting.

The piston and valve are about 135 degrees out of phase on the crankshaft (90 would be better).

Although it is by no means airtight, with high enough flow rates the leaks become negligible.

Very cool, and it seems to work pretty smooth! And powered by a hairdryer 

Thank you for sharing this 

That's really cool! Good job!

What a lovely design!

This is wonderful. Absolutely loved it !!!

A fairly simple construction, but works so well. I really need to build this with my son. I don't have too many system pieces, but hoping to manage it somehow.

And thank you so much for sharing extra images showing the airflow.

Edited April 23, 20213 yr by iLego

 

5 hours ago, iLego said:

This is wonderful. Absolutely loved it !!!

A fairly simple construction, but works so well. I really need to build this with my son. I don't have too many system pieces, but hoping to manage it somehow.

And thank you so much for sharing extra images showing the airflow.

Seconded... That's my activity this weekend with my kids sorted! They (and I) will love it... Thanks!

This is great! I saw a documentary on naval steam engines recently and this has inspired me to have a play with with various concepts.

Wow, that's amazing!

8 hours ago, iLego said:

A fairly simple construction, but works so well. I really need to build this with my son. I don't have too many system pieces, but hoping to manage it somehow.

 

2 hours ago, J159753 said:

Seconded... That's my activity this weekend with my kids sorted! They (and I) will love it... Thanks!

It has a 3D model on Mecabricks, if that would help:

https://mecabricks.com/models/Lkj9J03kvAp

Edited April 23, 20213 yr by Horologist

I loved it, it is unique and magnificent!!