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Title: Quiet power: Exploring the feasibility of a noise-mitigating, thermoacoustic energy harvester
The thermoacoustic effect provides a means to convert acoustic energy to heat and vice versa without the need for moving parts. This enables the realization of mechanically robust, noise mitigating energy harvesters, although there are limitations to the power-to-volume ratio achievable. The mechanical, thermal, and geometric properties of the porous stack that forms a set of acoustic waveguides in thermoacoustic devices are key to its performance. In this feasibility study, first, various 4-in. diameter ceramic and polymeric stack designs are evaluated using a custom-built thermoacoustic test rig. Influence of stack parameters such as material, length, location, porosity, and pore geometry are correlated to simulations using DeltaEC, a software tool based on Rott’s linear approximation. An acousto-thermo-electric transduction scheme is employed to harvest useable electrical power using the best performing stack. Steady-state peak voltage generated was 33.5 mV for a temperature difference of 34 °C between thehot and cold sides of the stack at an acoustic excitation frequency of 117.5 Hz. Further investigations are underway to establish structure-performance relationships by extracting scaling laws for power-to-volume ratio and frequency-thermal gradient dependencies.  more » « less
Award ID(s):
2033399
NSF-PAR ID:
10388363
Author(s) / Creator(s):
;
Date Published:
Journal Name:
The Journal of the Acoustical Society of America
Volume:
151
Issue:
4
ISSN:
0001-4966
Page Range / eLocation ID:
A179 to A179
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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