同轴型行波热声热机的实验研究

自行设计搭建了国际首台同轴型行波热声热机的实验装置 ,以氮气为工质 ,获得频率为1 3 7Hz的谐振声波。回热器热端温度达到 2 0 0℃左右时 ,热声热机开始起振 ,平均振幅 0 .1 4bar     

声学共振型行波热声发动机的实验研究

传统的行波热声发动机具有可靠性好、工质环保、潜在效率高等优点,但系统中存在一根体积较大的谐振管,降低了其功率密度及应用价值。本文设计并搭建了一台新型的声学共振型行波热声发动机,将三个相同的热声发动机核心单元连成环路,中间采用细长谐振管连接。实验中,发动机在100℃以下起振,频率约63 Hz,各压力下得到的最高压比均接近1.3,达到了传统行波热声发动机的最高压比。实验表明,新型的声学共振型行波热声发动机不仅具有传统行波热声发动机的优点,而且结构更加紧凑,具有更好的应用价值。     

热驱动室温行波热声制冷机的实验研究

本文报道了热声驱动的室温行波热声制冷机的实验研究。以氦气为工质研究了平均充气压力、工作频率等参数对制冷性能的影响。实验达到的最好结果为:最低温度为-47℃,在-20℃的制冷量为80W,按输入制冷机的P-V功计算,相应的制冷系数COP达到1.6左右。     

行波型热声热机的研究进展

Ceperley首先提出了行波型热声热机的概念 ,此后许多研究者对此类型的热机进行了理论及实验研究。文中对行波型热声热机的发展历史、研究现状及应用前景进行了简要介绍     

400W行波热声发电系统的实验研究

本文阐述了为太阳能发电系统设计的400 W行波热声发电系统(TWTAEG)的实验研究过程.实验系统由行波热声发动机和直线发电机组成,系统采用平均压力为3.5 MPa的氦-氩混合气体为工质,其中氩气分压比为1.4%,系统运行频率为74Hz.实验中最大输出电功为446 W,此时的热电效率为13%;在输出电功为416 W时热...     

行波型热声发动机起振温差的研究

热声机械作为一种新型的能量转化装置 ,讨论其起振温差对于利用低品位能源具有非常重要的意义。文中讨论了行波型热声发动机起振温差的计算方法 ,得到了回热器结构、工作介质、丝网、频率等对起振温差的影响规律     

行波热声发动机声功输出特性研究

行波热声发动机具有效率高、可靠性好及环保等优点.本文分别以氮气和氦气为工质研究了行波热声发动机的声功输出特性.在平均压力为3.0MPa,输入功率为3000W时,氮气为工质获得最大492.3W输出声功,氦气为工质获得最大691.3W的声功.此外还针对两种不同锥度的锥形谐振管发动机的声功输出特性进行了对比研究.研究表明:设计合理的谐振管一方面能够有效降低加热温度,有利于利用低品位热源;另一方面还能有效地降低损失,在相同的加热量下具有更高的压比、更大的输出声功及效率.     

高效室温行波热声制冷机的研究(第二部分:电声压缩机驱动的行波热声制冷机的实验研究)

热声制冷机是利用热声效应将声能转化为热能的新型制冷装置 ,以其环保性及高可靠性等优点吸引着起来越多的科研者。该文研究对象为电声压缩机驱动的室温行波热声制冷机。首先介绍了制冷机的工作原理、设计及加工 ;实验系统建立后 ,改装曲柄 -连杆活塞压缩机 ,使之提供变频的波动压力作为该制冷机的驱动源。初步实验在充气压力 2 .0 MPa、氦气为工质的工况下 ,获得 2 6 4 K的制冷温度     

行波热声发动机的优化设计

对行波热声发动机进行了优化设计 ;对回热器内部的功的损失和回热器的热漏损失进行了分析 ;给出了行波热声热机回热器的优化结构 ;对于设计行波型热声发动机有非常重要的理论指导意义。     

Investigation on the different types of resonators in the thermoacoustic Stirling prime mover

A new thermoacoustic Stirling prime mover consisting of a looped tube and different types of resonators respectively has been built. Experiments were focused on three axisymmetric types of resonators: cylinder, cone and cylinder-cone under the same operation conditions. Pressure ratios in the prime mover were observed, 1.15 for cylinder-cone, 1.092 for cylinder and 1.097 for cone. The acoustic fields along the looped tube and different types of resonators were calculated, which agreed well with the measured results.     

三级行波热声发动机的声场特性

设计并搭建了一台三级行波热声发动机,并基于线性热声理论和实验研究分析了该热声发动机的声场特性。结果表明:理论计算中各级加热功率相同时,发动机声场对称;而实验中加热功率相同时声场存在不一致性,需要输入特定的加热功率来控制三级加热温度基本相同,从而保证三级声场基本对称,此时相邻两级对应位置的压力相位差在120°±10°范围内;随着充气压力和加热温度的升高,系统工作频率略有升高,变化不显著,系统压力振幅和压比则增大明显。以氮气和氦气为工质时,工作频率分别在20 Hz和55 Hz左右;实验中压比分别达到了1.28和1.18。     

热声谐振管的实验研究

本文主要介绍作者热声谐振管研制方面的工作，作者成功地研制了热声谐振实验装置系统。     

Experimental study of the influence of different resonators on thermoacoustic conversion performance of a thermoacoustic-Stirling heat engine

In this paper, an experimental study of the effect of the resonator shape on the performance of a traveling-wave thermoacoustic engine is presented. Two different resonators were tested in the thermoacoustic-Stirling heat. One resonator is an iso-diameter one, and the other is a tapered one. To have a reasonable comparison reference, we keep the same traveling-wave loop, the same resonant frequency and the same operating pressure. The experiment showed that the resonator shape has significant influence on the global performance of the thermoacoustic-Stirling heat engine. The tapered resonator gives much better performance than the iso-diameter resonator. The tapered resonator system achieved a maximum pressure ratio of about 1.3, a maximum net acoustical power output of about 450 W and a highest thermoacoustic efficiency of about 25%.     

A study on a micro mover driven by ultrasonic waves

In developing a mobile micro robot, it is important to realize an effective energy supply method. The existing general method is to supply energy from outside through a cable. However, supplying energy through a cable adds weight and restricts movement. Mounted energy sources, such as batteries, also add weight. We therefore propose a method of supplying energy to a robot externally without using a cable. Using the radiation of ultrasonic waves as a wave energy source, we devised a mover that can receive and use wave energy for propulsion. We investigated and clarified the movement this prototype mover through various experiments. Consequently, we proved the use of ultrasonic waves to be effective as a cable-free energy supply.     

可调频率的热声振荡演示器的研制

基于热声理论,介绍了一种相对于传统热声振荡演示器更为简单、有效、直观的热声振荡演示装置,该装置除可调节声波振幅外,还可以调节声波的频率。该装置有助于更好地理解热声效应,了解影响热声振荡的因素,为进一步的深入研究奠定基础。     

Experimental modeling of the processes of active-passive thermoacoustic tomography

Experiments confirming the major results of the theoretical study of an active-passive mode of acoustic thermotomography are described. Experimental results are obtained with a setup intended for physical modeling of the processes of correlation reconstruction of the temperature, absorption, and phase velocity of sound in the object under investigation in the presence of an additionally introduced “illuminating” acoustic noise field. A possibility of reconstructing the local values of absorption and inhomogeneity of sound velocity from analyzing the correlation dependences based on difference and summary delays and also with the help of a controlled anisotropic acoustic irradiation is demonstrated.