Gas-water two-phase flow characterization with ERT and multivariate MLE

Gas-water two-phase flow widely exists in scientific researches and industrial production processes. Identification of flow regimes and understanding of inherent flow behaviors are significant to the accurate measurement of gas-water two-phase flow parameters. The maximum Lyapunov exponent (MLE) is a degree of quantitative description to a nonlinear dynamical system. Compared with single time series, the MLE of a multivariate time series provides more comprehensive information regarding the system´s dynamics. In order to characterize and identify the flow patterns of gas-water two-phase flow, the MLE of multivariate time series is extracted from an electrical resistance tomography (ERT). The MLE verifies that gas-water two-phase flow is a complex nonlinear dynamic system. The value of MLE can characterize and thus identify the flow pattern changes with the superficial velocity ratio of gas-water two-phase flow regime.