Terry Bastian
Thermoacoustic devices are versatile because they not only can cool,
<bold><italic><underline>but also can work in reverse as an
engine</underline></italic></bold>, Mongeau says.
"If you heat one side of the stack while keeping the other side cool, you
produce acoustic power, which could be converted to electricity or which
could power another acoustic driver to produce cooling elsewhere in the
system," he says. Mongeau demonstrates this principle in his lab by
dipping the open end of a device into liquid nitrogen, where it becomes
super-cold. "When we take it out, it warms up and a self-sustained
oscillation is created inside. <bold><italic><underline>It starts
singing.</underline></italic></bold>"
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