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Title: Traveling wave thermoacoustic refrigeration with variable phase-coordinated boundary conditions
Thermoacoustic refrigerators exploit the thermodynamic interaction between oscillating gas particles and a porous solid to generate a temperature gradient that provides a cooling effect. In this work, we present a resonator with dual enclosed driver end-caps and show that the temperature gradient across a ceramic thermoacoustic element placed in the cavity could be controlled by modifying the phase difference of the drivers, thus enabling precise control of the refrigeration capability via the temperature difference. Through DELTAEC simulation results, the response of the temperature gradient to various dynamic boundary conditions that alter the time-phasing and wave dynamics in the resonator are demonstrated. An experimental apparatus is constructed with two moving-coil speakers and a ceramic stack, which is shown to exhibit a temperature gradient along its length, based on the traveling-wave-like nature of the acoustic wave excited by the speakers. By adjusting the relative phase lag between the two speakers, the temperature gradient across the stack is made to increase, decrease, or flip sign. Finally, a desired temperature difference that changes in time is achieved. The results presented in this work represent a key conceptual advancement of thermoacoustic-based temperature control devices that can better serve in extreme environments and precision applications.  more » « less
Award ID(s):
1904254
PAR ID:
10482379
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
American Institute of Physics
Date Published:
Journal Name:
The Journal of the Acoustical Society of America
Volume:
154
Issue:
6
ISSN:
0001-4966
Page Range / eLocation ID:
3943 to 3954
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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