Abstract: Experiments were conducted on combustion instability in a modal combustor with vapor flame holder. Three equivalence ratios were chosen，0.4545，0.5454，0.6363，respectively. The pilot fuel percentage increases from 2% to 36% with interval 2%. The dynamic pressure transducers were used to measure combustor dynamic pressure frequency and magnitude at different equivalence ratios and different pilot fuel percentages. In order to compare with vapor flameholder，experiments were also conducted with V-gutter flameholder at three overall equivalence ratios. The results show that 130Hz and 203Hz instability modes are excited in vapor flameholder combustor. Only 203Hz instability mode is excited in V-gutter flameholder combustor. As pilot fuel percentage increases，the amplitude of 203Hz mode decreases at equivalence ratio 0.6363 while other modes amplitudes increase first and then decrease. The 130Hz and 203Hz modes are the 2nd and 3rd longitudinal acoustic modes，respectively，based on a one-dimensional combustor acoustic mode analysis.

Key words: Vapor flameholder；Combustion instability；Modal combustor；Pilot fuel

摘要： 对蒸发式火焰稳定器结构的模型燃烧室进行了燃烧不稳定性实验。实验中选取了3个当量比，分别为0.4545，0.5454，0.6363。每一个当量比中，值班级供油的比例从2%变化到36%，间隔为2%。利用动态压力传感器测量了不同当量比以及不同值班级供油比例时燃烧室内动态压力的频率和振幅。为了进行对比，在以上3个当量比时，也对普通V型稳定器进行了实验。结果显示，蒸发式稳定器激发了130Hz和203Hz两个不稳定模态。V型稳定器只激发了203Hz一个不稳定模态。总当量比不变时，随值班级供油比例的增加，除当量比0.6363工况的203Hz模态振幅呈现减小趋势，其他燃烧不稳定性模态的振幅均先增大后减小。对燃烧室进行了一维声学模态分析，130Hz和203Hz模态分别为系统的第2和第3阶纵向模态。

关键词: 蒸发式稳定器；燃烧不稳定性；模型燃烧室；值班级供油