Spatially distributed flame transfer functions for predicting combustion dynamics in lean premixed gas turbine combustors
Spatially distributed flame transfer functions for predicting combustion dynamics in lean premixed gas turbine combustors
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DOI：
10.1016/j.combustflame.2010.04.016
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发表时间：
2010-09
影响因子：
4.4
通讯作者：
Kyu Tae Kim;J. Lee;B. Quay;D. Santavicca
中科院分区：
文献类型：
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作者：
Kyu Tae Kim;J. Lee;B. Quay;D. Santavicca
本文描述了一种提高自诱发不稳定性特征频率和增长率预测准确性的方法，并演示了其在实验室规模、涡流稳定、稀薄预混燃气轮机燃烧室中的应用。使用局部火焰传递函数 (FTF) 测量来解释空间热释放分布的影响。双麦克风技术和 CH* 化学发光强度测量分别用于确定局部火焰传递函数的输入（入口速度扰动）和输出函数（热释放振荡）。利用火焰传递函数叠加原理将实验确定的局部火焰传递函数叠加，并将结果纳入解析热声模型中，以预测给定系统的线性稳定性特性。结果表明，当火焰长度在声学上不紧凑时，使用局部火焰传递函数计算的模型预测优于使用全局火焰传递函数做出的预测。在火焰处于紧凑火焰状态的情况下，可以使用全局火焰传递函数获得特征频率和生长速率的准确预测。研究还发现，局部 FTF（增益和相位）的一般响应特性在质量上与全局 FTF 的响应特性相同。
The present paper describes a methodology to improve the accuracy of prediction of the eigenfrequencies and growth rates of self-induced instabilities and demonstrates its application to a laboratory-scale, swirl-stabilized, lean-premixed, gas turbine combustor. The influence of the spatial heat release distribution is accounted for using local flame transfer function (FTF) measurements. The two-microphone technique and CH∗chemiluminescence intensity measurements are used to determine the input (inlet velocity perturbation) and the output functions (heat release oscillation), respectively, for the local flame transfer functions. The experimentally determined local flame transfer functions are superposed using the flame transfer function superposition principle, and the result is incorporated into an analytic thermoacoustic model, in order to predict the linear stability characteristics of a given system. Results show that when the flame length is not acoustically compact the model prediction calculated using the local flame transfer functions is better than the prediction made using the global flame transfer function. In the case of a flame in the compact flame regime, accurate predictions of eigenfrequencies and growth rates can be obtained using the global flame transfer function. It was also found that the general response characteristics of the local FTF (gain and phase) are qualitatively the same as those of the global FTF.