Ibrahim Abdelmaged H, Elbeltagy Khaled, Ramadan Islam, Ismail Omar A, Serag-Eldin M A, Abdel-Rahman Ehab
School of Science and Engineering, American University in Cairo, New Cairo 11835, Egypt.
Mechanical Power Department, Faculty of Engineering, Cairo University, Giza 12613, Egypt.
J Acoust Soc Am. 2024 Sep 1;156(3):1757-1768. doi: 10.1121/10.0028678.
A toroidal-topology traveling-wave thermoacoustic electric generator (TWTEG) is developed. It consists of a traveling-wave thermoacoustic engine, two linear alternators connected in parallel, and sets of variable resistive-capacitive (R-C) external electric loads, in conjunction with accessories and instrumentation required for experimental investigations. The working medium is helium with a static absolute pressure that varies from 25 bars to 30 bars. A detailed description of the thermal design of the heat exchangers is presented. Sustainable operation of the TWTEG is achieved over a range of external R-C loads at different imposed hot-side temperatures and mean gas pressures. The performance parameters are measured for different experimental conditions and compared with a developed lumped-element model. The comparison between the experimental results and predictions reveals a good agreement. The impedance matching between the thermoacoustic engine and the linear alternators is investigated experimentally over a wide range of external R-C loads. The external R-C loads play a crucial role in the operation of the TWTEG. The mean gas pressure changes the operating frequency; however, it has no significant influence on the operating range of the TWTEG on the R-C load map. Increasing the hot-side temperature improves the thermal-to-acoustic efficiency and extends the operating region into larger regions.
研制了一种环形拓扑行波热声发电机（TWTEG）。它由一个行波热声发动机、两个并联的线性交流发电机以及多组可变电阻电容（R-C）外部电负载组成，并配有实验研究所需的附件和仪器。工作介质为氦气，其静态绝对压力在25巴至30巴之间变化。给出了热交换器热设计的详细描述。在不同的施加热端温度和平均气体压力下，TWTEG在一系列外部R-C负载范围内实现了可持续运行。测量了不同实验条件下的性能参数，并与所建立的集总元件模型进行了比较。实验结果与预测结果之间的比较显示出良好的一致性。在行波热声发动机和线性交流发电机之间的阻抗匹配在很宽的外部R-C负载范围内进行了实验研究。外部R-C负载在TWTEG的运行中起着至关重要的作用。平均气体压力会改变工作频率；然而，它对TWTEG在R-C负载图上的运行范围没有显著影响。提高热端温度可提高热声效率，并将运行区域扩展到更大的区域。
