中文摘要：

对新型300 Hz质量片-膜环路双作用热声发动机的多单元结构进行了研究,详细考察了3单元、4单元、5单元、6单元结构下系统无负载和外接负载时的性能。系统无负载时,重点考察了发动机单元中核心参数的沿程分布;系统接负载时,重点考察了输出特性和最佳负载阻抗下加热功率对系统性能的影响。计算结果表明,增加环路双作用热声发动机的单元数会导致热声转换效率的降低,但能显著提高系统的输入加热功率,从而使系统获得更多的总输出声功。

英文摘要：

A novel multi-unit 300 Hz double-acting thermoacoustic heat engine was investigated,mainly by analyzing the non-load and on-load thermodynamic performance of the 3-unit,4-unit,5-unit,6-unit double-acting thermoacoustic heat engines. Based on thermoacoustic theory,the distributions of key physical parameters of the no-load system were presented for a better understanding of the energy conversion process in the multi-unit systems. Furthermore,the influence of input heating power on the on-load system performance was investigated under the optimal load impedances,which were determined by the output characteristics of the multi-unit systems. According to the calculated results,increasing the number of the units leads to the lower thermoacoustic conversion efficiency,but the total output acoustic power can be obtained because of more units used.