【作者】 严伟林；

【导师】 邱利民；

【作者基本信息】 浙江大学 ， 制冷与低温工程， 2005， 硕士

【摘要】 热声发动机利用热声效应,可实现从热能到声功的转换。用热声发动机取代常规的机械式压缩机来驱动脉管制冷机,可实现整个系统的完全无运动部件运行,是一种极具潜力的新型制冷方案。从1990年Swift和Radebaugh等人首先提出这个概念以来,热声发动机驱动脉管制冷机系统成为该领域的研究热点。 本文首先介绍了研究的背景和意义,简要回顾了热声系统的发展历史,并从定性和定量上对热声系统的原理进行了简单论述。本文提出了三种评价系统效率的方法,推荐采用(火用)效率对系统效率进行综合评价,这对系统的性能改善以及实用化研究具有一定的参考价值。 本文对自行研制的行波型热声发动机进行了研究,以氦气为工质,获得了1.19的最大压比,系统频率为73Hz。首次发现了外加扰动可降低热声系统起振温度的现象,并得到了实验验证,该方法对加深热声系统起振机理的认识及利用低品位热能提供了新的思路。 本文进行了热声发动机驱动脉管制冷机系统性能改进研究,获得了80.9K的最低制冷温度,这是当前该领域获得的最好结果之一。并对该热声发动机进行了声功测量,获得了122W的最大声功输出,为以后设计与该热声发动机具有良好匹配的新脉管制冷机提供了积极的指导。更多还原

【Abstract】 Thermoacoustic engine is a kind of machine, which can convert thermal energy into acoustic power by thermoacoustic effect. It is a new and promising way to drive a pulse tube cooler by a thermoacoustic engine instead of any other mechanical compressor so as to completely eliminate moving parts. It was firstly suggested by Swift and Radebaugh in 1990. After then, investigations on pulse tube cooler driven by thermoacoustic engine were widely made in the world.The background and significance of research are firstly given in the paper. After a brief review on developments of research, the principle of thermoacoustic system is also discussed qualitatively and quantitively. Three standards for system efficiency are introduced in the paper. Energy efficiency is recommended, which can provide instructive reference for the improvement and utility of thermoacoustic refrigeration system.Experimental study of the self-made traveling wave thermoacoustic engine has been done. When helium acts as working gas, the maximal pressure ratio of 1.19, and the operation frequency of 73 Hz are obtained. The phenomena that pressure disturbance can reduce the onset temperature of thermoacoustic engine is found and examined. The result is helpful to further understand the onset mechanism of thermoacoustic engine and use the thermal energy of lower temperature.After improving the system of pulse tube cooler driven by thermoacoustic engine, the lowest refrigeration temperature of 80.9K is obtained, which is one of the best results in the field. The acoustic power produced by the thermoacoustic engine is measured, and the maximal output of 122W is obtained, which can provide instruction for the design of new pulse tube cooler.更多还原