Novel Methods for Flame Pulsation Frequency Measurement with Image Analysis

To characterize the periodic pulsation of flame from the flame image sequence, several novel methods for flame pulsation measurement were introduced and demonstrated based on flame image analysis. Results show that moment function of flame image, such as weighted Euclidean distance and cross correlation coefficient, could represent the geometric and periodic flame pulsation; and that both the vertical and horizontal flame image slices (intersection of the cutting plane and the flame image sequence) evidently exhibit periodic texture resulted from flame oscillation. Flame pulsation frequency evaluated from flame image moment function, flame image slice and three-dimensional fast Fourier transform (FFT) is consistent and stable. For low instrument requirement and reliable performance, methods show great potential in flame diagnosis and monitor application.