Chill Out and Get Creamed with Coolest Mega Sound

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Researched by Industrialinfo.com (Industrial Information Resources, Incorporated; Houston, Texas). The deep freeze could go clean green on a chilling level of sound if work coming out of a Penn State research group translates to commercial applications. Under a grant from Unilever's Ben & Jerry's ice cream brand, Penn Sate acousticians have achieved proof of a concept for a compact ice freezer case based on green technology that substitutes sound waves for environmentally damaging chemical refrigerants.

The group's findings were released in a paper 'Performance of a small low-lift regenerator-based thermoacoustic refrigerator' at the recent First Pan-American/Iberian Acoustics meeting in Cancun, Mexico. In the proof of concept test system, there is no test freezer. An electrically piece of window screen is cooled. The coldest temperature we have achieved is minus eight below zero, well below the freezing point of water.

The group's thermoacoustic chiller uses a souped-up loudspeaker to generate high amplitude sound energy in an environmentally safe gas (the test model uses ordinary air) that is converted into useful cooling. The high amplitude sound levels are hundreds of thousands of times beyond the levels reached at rock concerts.

Looking ahead to commercial and industrial applications it is crucial that no sound energy escapes from the system. The high sound levels can only be generated by the resonance conditions maintained by the pressurized gas.

The United Technologies Corporation professor of at the renowned Penn State acoustics faculty, Dr Steven Garrett, says that they have been operating loudspeakers at resonance and using bellows in thermoacoustic devices for 20 years. Now, by putting the entire refrigeration core inside the bellows, the size has been substantially reduced.

The leading process engineer at Ben&Jerry, Gay Epright, has hailed the research as a tremendous opportunity to participate in an innovative technology that could revolutionize the way refrigeration is understood and used. Based on sound and using environmentally safe gases will assist in restoring atmospheric balances.

Just as two researchers at Birmingham University, UK, in the 1930's could never have envisaged their breakthrough creation of cavity magnetron would lead to quantum development of radar and then to the microwave cooker the Penn State team may have spawned a whole train of industrial and commercial developments for the future.

"How does the idea of an ice cream resonate with you, honey?" he said, shouting as loudly as he could into the thermoacoustic chiller, against the sound of heavy metal at top volume, from the kitchen.