以单级轴向旋流丙烷扩散火焰模型燃烧室为研究对象,对不同旋流数、不同进气雷诺数的扩散火焰不稳定燃烧的振荡边界变化规律进行了研究.并对试验结果采用快速 FFT、峭度分析及 POD 分解等方法进行分析,重点分析了旋流数对扩散火焰振荡边界临界当量比的变化趋势影响.试验结果表明:系统从稳定燃烧状态过渡为振荡燃烧状态的临界当量比随着旋流数的增加而逐渐增加,同时也随着空气进气雷诺数的增加而增加,即旋流数越大或雷诺数越大,稳定燃烧区域越窄,越容易产生燃烧不稳定.此外也发现振荡边界的压力脉动主频会随着旋流数的增加而增加,同样也会随着雷诺数的增加而增加.
Influence of Swirler Parameters on Combustion Instability Boundary
Using a single-stage axial swirling propane flame model combustor as the research object,the oscillat-ing boundary variation law of diffusive flame unstable combustion with different swirl numbers and different inlet Reynolds numbers was studied.The experimental results were analyzed by means of fast FFT,kurtosis analysis and POD decomposition.The effect of vortex number on the critical equivalence ratio at the oscillating boundary of the diffuse flame was analyzed.The experimental results show that the critical equivalence ratio of the system tran-sitioning from a stable combustion state to an oscillating combustion state gradually increases with the increase of both swirl number and air intake Reynolds number.That is,the larger the swirl number or Reynolds number,the narrower the stable combustion region,and the easier it is to produce combustion instability.In addition,it was also found that the main frequency of pressure pulsation at the oscillating boundary increases with the increase of both swirl number and Reynolds number.
万方数据
维普
