A Sterling Engine is a closed system. The \"hot\" side oscillates between higher

Question

A Sterling Engine is a closed system. The "hot" side oscillates between higher temperature with higher pressure and lower temperature with lower pressure. Does Nature switch back and forth between one temperature/pressure combination and another temperature/pressure combination without loss of energy within the closed system?

The International Sterling Engine Society says they can get 60 Watts from a 50 degree temperature differential. Is there the equivalent of 60 Watts of power pulled from the hot tank? If not, where does the 60 Watts come from?

Explanation / Answer

A Stirling engine moves a fluid from a hot end to a cold end - extracting mechanical work as it does so. The power input comes from maintaining the temperature of the hot end - usually by burning some fuel externally.

The 'clever' part of a Stirling engine, and the thing that gives it it's high efficiency, is that the hot end of the mechanism stays hot and the cold part stays cold, so you don't waste energy constantly re-heating a piston

enter image description here

image from http://en.wikipedia.org/wiki/Stirling_engine - It's an alpha type engine, less common in practice but easier to understand

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.