Joo Seongpil, Choi Jongwun, Kim Namkeun, Lee Min Chul
Gas Turbine Laboratory, National Research Council of Canada, Ottawa, ON, Canada.
Department of Mechanical Engineering, Incheon National University, Incheon, 22012, Republic of Korea.
Sci Rep. 2021 Feb 4;11(1):3043. doi: 10.1038/s41598-020-80427-6.
This study proposes and analyzes a novel methodology that can effectively detect multi-mode combustion instability (CI) in a gas turbine combustor. The experiment is conducted in a model gas turbine combustor, and dynamic pressure (DP) and flame images are examined during the transition from stable to unstable flame, which is driven by changing fuel compositions. As a powerful technique for early detection of CI in multi-mode as well as in single mode, a new filter bank (FB) method based on spectral analysis of DP is proposed. Sequential processing using a triangular filter with Mel-scaling and a Hamming window is applied to increase the accuracy of the FB method, and the instability criterion is determined by calculating the magnitude of FB components. The performance of the FB method is compared with that of two conventional methods that are based on the root-mean-squared DP and temporal kurtosis. From the results, the FB method shows comparable performance in detection speed, sensitivity, and accuracy with other parameters. In addition, the FB components enable the analysis of various frequencies and multi-mode frequencies. Therefore, the FB method can be considered as an additional prognosis tool to determine the multi-mode CI in a monitoring system for gas turbine combustors.
本研究提出并分析了一种能够有效检测燃气轮机燃烧室中多模态燃烧不稳定性（CI）的新方法。实验在模型燃气轮机燃烧室中进行，在由燃料成分变化驱动的火焰从稳定向不稳定转变过程中，对动态压力（DP）和火焰图像进行了检测。作为一种在多模态以及单模态中早期检测CI的强大技术，提出了一种基于DP频谱分析的新型滤波器组（FB）方法。采用具有梅尔标度的三角滤波器和汉明窗进行顺序处理，以提高FB方法的准确性，并且通过计算FB分量的大小来确定不稳定性准则。将FB方法的性能与基于均方根DP和时间峰度的两种传统方法的性能进行了比较。结果表明，FB方法在检测速度、灵敏度和准确性以及其他参数方面表现出相当的性能。此外，FB分量能够分析各种频率和多模态频率。因此，FB方法可被视为燃气轮机燃烧室监测系统中确定多模态CI的一种额外的预后工具。
