Performance of a small, low-lift regenerator-based thermoacoustic refrigerator

Abstract

A regenerator-based thermoacoustic refrigerator [Swift, Gardner, and Backhaus, ‘‘Acoustic recovery of lost power in pulse tube refrigerators,’’ J. Acoust. Soc. Am. 105(2), 711 (1999)] has been constructed. It is capable of moving about 5 W across a 40<th>°C temperature span. The machine operates with air at atmospheric pressure and is driven by an off-the-shelf electro-dynamic loudspeaker capable of producing peak-to-mean pressure ratios up to 12%. The thermal core of this research device contains an exhaust-side shell and tube heat exchanger (with water as the secondary heat transfer fluid), a regenerator made of 88 annular stainless-steel screens, and a constantan wire electrical heater that applies a measurable heat load to the cold side of the regenerator. An annular latex diaphragm is placed over the cold side of the regenerator to stop time-averaged mass flow through the regenerator and insulate the cold side [Gedeon, ‘‘DC Gas Flows in Stirling and Pulse Tube Cryocoolers,’’ in Cryocoolers 9, edited by R. G. Ross (Plenum, New York, 1997)]. Detailed measurements of heat load, temperature span, and exhaust heat flux will be presented and compared to DeltaE. [Work supported by ONR.]