Wavelet entropy applied in gas-liquid two-phase flow

The two-phase flow type characteristics in a vertical gas-liquid two phase flow based on the wavelet entropy algorithm are studied in this paper. First of all, the gas-liquid two-phase flow conductance sensor fluctuation signal are collected in a vertical tube of radius 125mm. The newly developed vertical multi-electrode array of eight electrodes conductance sensor measurement system is used to collect the signal. Then, the conductance sensor fluctuation signal is decomposed by a wavelet transform. In this paper, Daubechies wavelet series is used to decompose the signal, and the decomposition scale is eight. Wavelet coefficients of each scale are calculated, and wavelet energy values are calculated for the wavelet coefficients. Finally, wavelets entropy values are calculated. Wavelet entropy connects wavelet analysis and entropy theory, and thus has the advantages of both. Through the wavelet entropy, analysis, flow characteristics of the five flow patterns in gas-liquid two-phase flow (bubble flow, bubble- slug flow, slug flow, slug - churn flow, churn flow) are extracted. This field is a new research field and it can be attributed to the flow feature extraction and analysis.