负载阻抗对热声发动机性能影响分析

Influence of load impedance on performance of thermoacoustic engine

为了探索负载的阻抗特性对热声发动机性能的影响,利用线性热声理论,对驻波型热声发动机驱动阻容负载进行了数值模拟.根据模拟计算结果,分析讨论了阻容负载的阻抗对热声发动机的压力振幅、压比、速度振幅、板叠热端温度以及传递给负载的声功率等性能的影响.在模拟计算的基础上,进行了热声驱动阻容负载的初步实验.计算和实验结果表明,当负载的声阻与容抗相等时,热声发动机向阻容负载传递的声功率最大,此时,负载入口处的压力振幅和压比最小,板叠热端温度最高;阻容负载容抗越小,对应的声功率和板叠热端温度的峰值越大,而压力振幅和压比的谷值越小.

A standing wave thermoacoustic engine connected with an RC （acoustic resistance and acoustic capacitance） load was simulated with linear thermoacoustics to study the influence of load impedance on the performance of the thermoacoustic engine. Based on the computed results, the effects of the load impedance on pressure amplitude, pressure ratio, velocity amplitude, temperature at the hot end of stack and acoustic power transferred to the load were discussed. Experiments were performed to verify the simulation. The computed and experimental results showed that maximal acoustic power can be transferred to the load when the acoustic resistance of the RC load is equal to its acoustic capacitive impedance. Moreover, a minimal pressure amplitude and a highest temperature at the hot end of stack occur in this case.