Study on the statistical analysis methodology of the swirl flame dynamics

Combustion instability is now being widely studied. Combustion instability includes static and dynamic instability. On dynamic instability, the traditional research methods are to measure the dynamic pressure and heat release of the swirl flame through experiments, and then the experimental results are obtained by Fast Fourier Transform, and the influence of the parameters on the pressure fluctuation and the thermal acoustic oscillation is obtained. However, this method has some defects, such as the large error, the dynamic characteristics of the flame is not intuitive and so on. Therefore, a statistical image processing method can be developed based on large sample size to describe the flow characteristics of swirl flame. By using two methods of proper orthogonal decomposition and dynamic mode decomposition, the dynamic characteristics of the swirl flame are described. Meanwhile, due to the large sample size, the error of processing experimental data is small.