Hi
What material is preferred for a displacer body for a Stirling engine ?
Can this be aluminium?
I need to machine this on my hobby lathe.
The tube is about 16mm dial by about 40mm long with a minimal wall thickness.
Thanks
Displacer body
Re: Displacer body
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Usually, if available stainless steel. It can be found in thrift stores in various items, like pots, thermoses, thermos coffee cups, etc. it is thin strong and heat, and rust, resistant.
You want it to be conductive into the gas, yet non conductive lengthwise. Longer cylinders are better for high temperatures. Pancake shaped cylinders are better for low temperatures. The compression ratio should match the temperature ratio that you plan to operate the engine.
Other displacer cylinder materials would be thin walled steel, like a tin can. Thin walled aluminum, like a pop can. Propane or butane bottles, glass, test tubes. Even acrylic has been used in low temperature engines. Copper pipe is too conductive length wise, unless a thermally insulated mid section is used.
.
Usually, if available stainless steel. It can be found in thrift stores in various items, like pots, thermoses, thermos coffee cups, etc. it is thin strong and heat, and rust, resistant.
You want it to be conductive into the gas, yet non conductive lengthwise. Longer cylinders are better for high temperatures. Pancake shaped cylinders are better for low temperatures. The compression ratio should match the temperature ratio that you plan to operate the engine.
Other displacer cylinder materials would be thin walled steel, like a tin can. Thin walled aluminum, like a pop can. Propane or butane bottles, glass, test tubes. Even acrylic has been used in low temperature engines. Copper pipe is too conductive length wise, unless a thermally insulated mid section is used.
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