Abstract: This paper studies dynamic pressure signals from the state far from surge to the state of fully developed surge in the centrifugal compressor using a correlation integral method to quantify various stages in the surge development. The measured data in the transitional stage and the surge stage are analyzed using FFT to obtain the exact frequency of surge and its precursor with high-resolution spectrum. Variation of the spectrum peak with time in the fixed zoom region is obtained through a continuous spectral analysis. It is illustrated that the dominant frequency in the transitional stage and the surge stage fluctuates mildly around these two frequencies.

Key words: centrifugal compressor, surge, correlation integral, FFT