Green Chillies: Refrigerant-Free Acoustic Cooling for HVAC&R Applications

Keywords:
HVAC, acoustic, refrigeration, cooling

Abstract:
Acoustic cooling uses the pressure oscillations of sound in an inert gas, and the associated temperature swings, as the basis for environmentally benign cooling/heat-pumping technology. This approach has been proven first in cryogenic applications, and more recently demonstrated for food storage refrigeration. Air-conditioning versions are now under development. Applicable wherever conventional equipment is used, acoustic coolers approach Stirling-cycle efficiencies without complex mechanics; providing improved performance with no oil, no conventional refrigerants, and minimal maintenance. This paper introduces the core technology, explaining how high-frequency replaces high enthalpy in the working fluid to maintain capacity in units sized for drop-in replacement, without conventional phase-change refrigerants. We provide results from extended uses in cryogenics and long-term testing of a prototype food-storage device; plus projections of configurations, performance, and costs for rooftop or PTAC units for HVAC use.

Nanotech 2008 Conference Program Abstract