

Thermoacoustic heat engine - mojoe
http://en.wikipedia.org/wiki/Thermoacoustic_heat_engine

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mojoe
Sounds are pressure waves in air, and you can create varying densities of air
by heating and cooling, but I never put the two facts together and realized
that you could create an engine that way.

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jessaustin
See
[http://www.mme.wsu.edu/~matveev/tae.htm](http://www.mme.wsu.edu/~matveev/tae.htm)
for some idea of what these might look like.

