"In our proof-of-concept test system, there is no 'test freezer,' we simply cool an electrically-heated piece of window screen. The coldest temperature we have achieved with this test rig is eight degrees below zero – well below the freezing point of water," Garrett says. However, although the test rig doesn't look anything like the freezer display case where you usually pick up your pint of Cherry Garcia, Garrett says it is a big step in the "green" ice cream sales cabinet direction.
"We have achieved proof-of-concept for making a compact chiller that has a volume which is substantially smaller than earlier thermoacoustic chillers," he explains. "And we did it with a system that was carefully and redundantly instrumented for both accurate performance measurement and performance diagnostics."