Induced and transferred charge signals decoupling based on discrete wavelet transform for dilute gas-solid two-phase flow measurement

Abstract

The inner flush-mounted electrostatic sensors are widely used in gas-solid two-phase flow measurement. The measuring signals are made up of induced charge signal and transferred charge signal. This paper presents a decomposition method of measuring signals based on discrete wavelet transform (DWT). According to the characteristics of induced and transferred charge signals, cD5∼7 signal components are chosen to reconstruct induced charge signal. Because the induced charge signals from the upstream and downstream electrodes have high similarity, the method is evaluated by correlation coefficient. The results show that the decoupled induced charge signals from upstream and downstream electrodes have a mean correlation coefficient of 0.73, which is higher than that of measuring signals without decomposition. In addition, the relative error is reduced by 0.5% when comparing to the empirical velocities of IGT and 3.1% when comparing to the empirical velocities of Hong and Hinkle after signal decomposition and reconstruction.