Flow regime identification methodology with neural networks and two-phase flow models

Vertical two-phase flows often need to be categorized into flow regimes. In each flow regime, flow conditions share similar geometric and hydrodynamic characteristics. Previously, flow regime identification was carried out by flow visualization or instrumental indicators. In this research, to avoid any instrumentation errors and any subjective judgments involved, vertical flow regime identification was performed based on theoretical two-phase flo w simulation with supervised and self-organizing neural network systems. St atistics of the two-phase flow impedance were used as input to these system s. They were trained with results from an idealized simulation that was mai nly based on Mishima and Ishii's flow regime map, the drift flux model, and the newly developed model of slug flow. These trained systems were verifie d with impedance signals measured by an impedance void-meter. The results c onclusively demonstrate that the neural network systems are appropriate cla ssifiers of vertical flow regimes. The theoretical models and experimental databases used in the simulation are shown to be reliable. Published by Els evier Science B.V.