扬声器对Rijke型燃烧器热声不稳定控制效果的研究  

Investigation on control effects of loudspeaker on the thermoacoustic instability in a rijke combustor

作　　者：周昊[1] 黄燕[1] 丁芳[1] 王恒栋[1] 岑可法[1] 

机构地区：[1]浙江大学能源清洁利用国家重点实验室,杭州310027

出　　处：《振动与冲击》2016年第22期66-71,共6页Journal of Vibration and Shock

基　　金：国家重点基础研究发展计划(2015CB251501)

摘　　要：扬声器布置在Rijke管型燃烧器入口和出口处,输出不同频率和声压级的声波可以对热声不稳定进行开环主动控制。试验发现在热声管燃料入口燃料管路布置扬声器是一种有效的热声不稳定主动控制方法,扬声器发出的声波可以使热声不稳定的压力振荡有所衰减,同时也会产生新的和声波同频的压力振荡;在某些工况下,和声波同频的压力振荡幅值甚至会高于热声不稳定的压力振荡幅值;在该试验中,当扬声器声波频率为50 Hz、声压级为100 d B时,控制效果最好,达到38.55%。布置在热声管开口端的扬声器也是一种有效的热声不稳定主动控制方法,在该试验中,当扬声器声波频率为300 Hz、声压级为115 d B时,控制效果最好,此时控制效果可达34.58%。Loudspeakers were used for active control of the thermo acoustic instability in combustors.The loudspeakers were placed on the fuel inlet and outlet of a Rijke tube type of combustor to output acoustic frequencies and sound pressure levels for the open-loop active control of thermoacoustic instability.It is found that loudspeakers placed on the fuel inlet pipe is an effective method to control the thermoacoustic instability in the Rijke combustor.Sound waves from the loudspeaker could attenuate the thermoacoustic pressure oscillations.At the same time,a new pressure oscillation is generated by sound waves with the same frequency of sound waves.In certain experiment cases,the amplitude of the new pressure oscillation caused by sound waves could be higher than that due to thermoacoustic instability.In the experiment case with sound frequency of 50 Hz and sound pressure level of 100 dB,the efficiency of pressure amplitude reduction can reach 38.55%.Placing loudspeakers on the open end of the Rijke combustor is also an effective way.In the experiment case with sound frequency of 300 Hz and sound pressure level of 115 dB,the efficiency of pressure amplitude reduction can reach 34.58%.

关 键 词：扬声器 Rijke 型燃烧器 热声不稳定 控制效果 

分 类 号：TK124[动力工程及工程热物理—工程热物理] TH213.3[动力工程及工程热物理—热能工程]