Identification of complex compliance for regenerator in thermoacoustic resonator system

Abstract

In thermoacoustic system, the characteristic of complex compliance of a regenerator has a great influence on energy stored and dissipation of the whole engine. In order to investigate the performance of regenerators with different matrix geometries and materials coupled with different acoustic systems, an experimental measurement and analysis method was presented. By measuring the resonant frequency, the complex compliance and quality factor of five kinds of matrix were experimentally analyzed respectively in the system of loudspeaker-driven thermoacoustic resonator (TAR) with different lengths. The experimental results show that the real part of complex compliance of the regenerator with pin-array has a maximum value among the measured matrixes and its quality factor is the largest (28.222) with the least dissipation factor of 0.035 4. So the pin-array matrix is testified to behave more excellently on the energy conversion than other matrixes. Compared with other factors the complex compliance of a regenerator contributes more to the performance of a thermoacoustic system.

Keywords

thermoacoustic / regenerator / resonant frequency / complex compliance / quality factor

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