带声学放大器的行波热声发动机声阻抗特性  

Acoustic impedance characteristics of traveling wave thermoacoustic engine with acoustic amplifier

作　　者：董世充 徐漠北 沈国清[1] 张世平[1] 安连锁[1] DONG Shi-chong;XU Mo-bei;SHEN Guo-qing;ZHANG Shi-ping;AN Lian-suo(School of Energy, Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China)

机构地区：[1]华北电力大学能源动力与机械工程学院

出　　处：《声学技术》2019年第5期488-494,共7页Technical Acoustics

基　　金：中央高校基本科研业务费专项资金资助2017ZZD001

摘　　要：通过分析带有声学放大器的行波热声发电系统中直线发电机的电-力-声类比图,发现直线发电机的最佳工作状态与行波热声发动机的输出声阻抗特性相关。采用DeltaEC软件计算带有声学放大器的行波热声发动机(以下简称系统)的输出声阻抗特性。计算结果发现,输出声阻抗虚部Xa为.1×107Pa·s·m^-3时,系统的最大输出声功率545.47W,最大热声转换效率为7.2%;当输出声阻抗虚部Xa在.3.9×106~.1×107Pa·s·m^-3之间变化,实部Ra在1.37×106~2.31×107Pa·s·m^-3之间时,等效位移在1.89~6mm之间变化,符合直线发电机的位移要求;结合输出声阻抗对压力与体积流率的相位差及系统工作频率的影响,发现声阻抗实部Ra应在1.37×106~2.31×107Pa·s·m^-3之间,声阻抗虚部Xa在.7.5×106~.1.0×107Pa·s·m^-3之间时,系统具有较好的工作状态。In this paper it is found that the optimal working state of a linear alternator is related to the output acoustic impedance characteristics of the traveling wave thermoacoustic engine by analyzing the electric-force-acoustic analogy of the linear alternator in the traveling wave thermoacoustic power generation system with an acoustic amplifier (here- inafter referred to as system). The output acoustic impedance characteristics of the system are calculated by using DeltaEC software. The calculation results show that when the imaginary part of the acoustic impedance is Xa= 1×10 7 Pa s m^-3, the maximum output sound power of the system is 545.47 W, and the maximum thermoacoustic conversion efficiency is 7.2%. When the imaginary part X a of the output acoustic impedance varies from 3.9×10 6 to 1×107 Pa s m^-3 and when the real part R a varies between 1.37×106 and 2.31×107 Pa s m^-3, the equivalent displacement varies from 1.89 to 6 mm, which meet the displacement requirements of linear alternators. Combined with the influence of output acoustic impedance on the phase difference between pressure and volume flow rate and the operating frequency of the system, it is found that when the real part R a of acoustic impedance is in the range of 1.37×10 6 to 2.31×107 Pa s m^-3 and when the imaginary part X a of the acoustic impedance is between 7.5×106 and 1.0×107 Pa s m^-3, the system has a good working condition.

关 键 词：声学放大器 行波热声发动机 直线发电机 声阻抗 

分 类 号：TK121[动力工程及工程热物理—工程热物理]