高频热声制冷机中的压电喇叭特性

Characteristics of piezoelectric loudspeakers in high frequency thermoacoustic refrigerator

研究建立了1台5 kHz微型热声制冷实验样机,对压电喇叭谐振系统的阻抗特性,以及频率和电压响应特性进行了实验研究。初步的实验显示,压电喇叭与驱动电源和热声谐振系统之间需要在电学和声学上进行匹配,PZT5的压电陶瓷材料发热较大,且提供的声功率较小,这些是影响微型制冷的重要因素。

A miniature thermoacoustic refrigerator prototype with a frequency of 5 kHz was constructed.Some experiments were carried out to investigate the impedance characteristic, the frequency and the voltage response of a bimorph piezoelectric loudspeaker with a thermoacoustic resonant system. The preliminary experiments demonstrated that the matching of piezoelectric loudspeaker electrically and acoustically are needed with the driving electric source as well as the thermoacoustic resonant system.The piezoelectric material of PZT5 has much thermal production and small acoustic power output. All of these are of important factors to affect the cooling of a miniature thermoacoustic refrigerator.