【摘要】 在CH4与空气的化学当量比为0.7、空气量为25 m/s时进行了旋流燃烧器热声振动试验.分析了不同中心风量下旋流燃烧的热声不稳定特性.结果表明:在中心风量为10%时,旋流核心区明显受到中心射流的影响,热声振动振幅明显下降,最大峰值脉动压力下降216 Pa;中心射流对热声振动的影响存在一个阈值,提高射流速度可使中心射流作用于旋流核心区,从而影响燃烧与声波的耦合,以实现对热声振动的被动控制.更多还原

【Abstract】 Thermoacoustic oscillation experiment of swirl combustor was carried out with chemical equivalent ratio of 0.7 for CH₄ to air and the air flow of 25 m/s.The thermoacoustic instability of the swirl combustion was analyzed with different flow rates of the central jet.Results indicate that,when the flow rate of the central jet is 10% of the total,the swirl core was obviously affected,resulting in a clear decrease of amplitudes of thermoacoustic oscillations.The maximum peak of the oscillating pressure decreases 216 Pa.There existes a threshold value for the effects of central jet on thermoacoustic oscillation.Increasing the jet velocity would make the central jet act on the core area of swirl.Thus it can affect the couple of combustion and acoustic wave to realize the passive control to the thermoacoustic oscillation.更多还原