Heavy or lightweight displaser for more horsepower?

[Wellington]

Hello all. i want to build a stirling that produces good horsepower. Should i use a light weight displacer or a heavy displacer?
Thanks All. Regards
Wellington.

[Trevor]

Hi Wellington
A displacer that is extra light weight is very beneficial. Make it light as possible yet sturdy and do not use aluminium as the displacer as in high heat they will melt or distort badly. Ian can show you some photos of what can happen using alloy as a displacer.
Trev

[Ian S C]

Wellington, yes use light weight steel, or stainless steel. Weight just causes extra friction, also the thicker metal conducts heat along it faster than thin metal. The thin metal acts as a regenerator picking up and dropping heat as the air goes past.
As Trev says, don't use aluminium if you want any power out of the motor, it will work as long as you don't use too much heat.
Ian S C
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[Wellington]

Hi Wellington
A displacer that is extra light weight............
Trev

Thank Trevor. will steer clear of aluminium displacer.
regards
Wellington

[Wellington]

Wellington, yes use light weight steel, or stainless steel. Weight just causes extra friction....................
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Yep. I imagine the friction would go up. On another note: I remember once seeing a german website which sold lots of different stirling engines but can no longer find it. Any ideas which website that might be?
Wellington

[Ian S C]

I think the German outfit you are thinking of may be Bohm. I bought one from Jaycar a couple of years ago, looks ok, but a bit feable.
Ian S C
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