Hilbert–Huang Transform-Based Electrostatic Signal Analysis of Ring-Shape Electrodes With Different Widths

Online measurement of the particulate flow plays a significant role in the monitoring and controlling process of the industrial application. Due to the simple structure and high sensitivity, the electrostatic method is widely used in the measurement of the gas-solid two-phase flow. The ring-shape electrodes with different widths have different sensitivity distributions. The electrostatic signals from the electrodes of 2- and 10-mm axial widths were obtained from experiments conducted on the gas-solid two-phase flow rig. Because of the advantages of the Hilbert-Huang transform, it was utilized to investigate the characteristics of the electrostatic signals from different electrodes and to extract the features to characterize the change of solid concentrations. Considering the correlation coefficient between the features and the solid concentrations and the features´ linear performance under different air flow rates, the energies of the intrinsic mode function 3 from different signals were extracted to characterize the change of solid concentrations.