Mk II heat engine made from cans

My second attempt at a heat engine, building on the lessons learnt from the Mk I (also on youtube). Improvements this time:

The cold end (top) of the cylinder has a small open tray for ice/water.

The crank arrangement is more rigid.

The large cylinder uses a seamless can as the Mk I was leaking at the base after receiving too much flame.

The geometry of the displacer linkage has been changed with the stroke halved to 22mm and a longer connecting rod this has reduced the angle the con rod has to adopt as this was causing friction in the crosshead. In this version the crosshead is also longer with an additional upper bearing, although this proved unnecessary.

Observations on this effort:

Friction remains a problem although tolerances are much improved and I was determined to keep this very basic; further improvement would require ball races and better materials for power piston/cylinder.

The knocking noise is due to a sloppy connection at the top of the power piston so this is loosing energy.

Although the cooling tray keeps the top of the cylinder cool the sides right up to the top still get very hot so this needs improvement.

Category:

Entertainment

Tags:

• stirling
• engine
• heat
• hot
• air
• model

[HanzoHk85]

care to explain how it works

[sciencejunk]

There are many sites on the net that explain this fully, some have nice animations. Basically, the system is air-tight and the air is heated then cooled during each cycle. While hot the air expands pushing the small piston up, while cool it contracts pulling it down. The crank drives a displacer (inside the can) which moves air between the hot and cold ends at the correct time.

I hope this helps.

[millennians]

If you were to invert a wineglass that could seperate water into Hydrogen snd Oxygen, and recombine them, your heat engine could generate static electricity and it would have the same kind of motion that throwing a rock in space would achieve, perpetual... After all, the Earth is doing it!

[441rider]

Very nice! I hope to have as good a result from mine when assembled.