摘要
为验证旋转爆震波与燃烧室高频切向不稳定燃烧现象是否存在一致性,分别基于宽11 mm的环形燃烧室和圆柱形燃烧室,以乙烯为燃料,以富氧空气(体积分数33%、50%和100%)为氧化剂,通过改变氧化剂的供给流量和当量比开展实验研究。研究发现:在环形燃烧室中,通过改变氧气体积分数得到了不同的旋转爆震波传播模态:当氧气体积分数为33%时为双波对撞模态,爆震波速度亏损为37%~63%,且双波传播频率低于燃烧室二阶切向声学频率;当氧气体积分数为50%和100%时,分别得到了单波和双波传播模态,爆震波速度亏损减小至14%~40%,且单波模态爆震波传播频率高于燃烧室一阶切向声学频率,双波模态爆震波传播频率高于燃烧室二阶切向声学频率。在圆柱形燃烧室中,当氧气体积分数为50%时得到了单波模态,部分工况下爆震波传播速度高于理论C−J速度,且氧化剂流量越大,这一趋势越明显,大部分工况下旋转爆震波传播频率均高于燃烧室的一阶切向声学频率。上述研究表明旋转爆震波传播频率与燃烧室切向声学频率的数值大小和变化规律均不相同,说明旋转爆震波与高频切向不稳定燃烧现象并不存在一致性。
To verify the relationship between rotating detonation waves and the intrinsic high-frequency tangential instability of the combustor,this experimental study has been conducted inan annular combustor with the width of 11 mm and a hollow combustor.Oxygen-enriched air,with the volume fractions of 33%,50%and 100%,and ethylene have been used as propellants.Inthe annular combustor,three propagation modes have been observed as the different volumefractions of the oxygen-enriched air have been used.The dual-wave collision mode has beenobtained as the oxidizer of 33%O2 has been utilized.In this propagation mode,the velocitydeficit is around 37%–63%and the values of the dual-wave propagation frequency are lower thanthe intrinsic second order tangential frequency.As the volume fraction of the oxidizer increasingfrom 50%to 100%,the single detonation mode and two detonation waves mode have beenobtained.The velocity deficit is around 14%–40%for the unidirectional propagation detonations.The propagation frequency values of the single detonation mode and two detonation waves modeare obviously higher than the value of the intrinsic first order and second order tangentialfrequency,respectively.In the hollow combustor,the single detonation mode has been obtainedwhen the oxidizer of 50%O2 has been adopted.It is observed that the propagation velocities arehigher than the theoretical C−J velocity and the propagation frequency values are higher than theintrinsic first order tangential frequency in most cases.In summary,the propagation frequencyvalues calculated from different propagation modes of rotating detonation waves are obviouslydifferent from the intrinsic tangential frequency of the combustor and this result indicates thatthe discrepancy between rotating detonation waves and high-frequency tangential instabilities isevident.
作者
王致程
严宇
范玮
王可
杨宝娥
胡洪波
WANG Zhicheng;YAN Yu;FAN Wei;WANG Ke;YANG Bao'e;HU Hongbo(National Key Laboratory of Aerospace Liquid Propulsion,Xi'an Aerospace Propulsion Institute,Xi'an 710100,China;School of Power and Energy,Northwestern Polytechnical University,Xi'an 710072,China)
出处
《实验流体力学》
CAS
CSCD
北大核心
2024年第2期68-77,共10页
Journal of Experiments in Fluid Mechanics
