Flow pattern identification of oil/water two-phase flow based on kinematic wave theory

Abstract Based on the kinematic wave theory, the kinematic wave propagation velocity ( C k ) equation is established for oil/water two-phase flow in vertical upward pipes. The phase distribution coefficient C o and the bubble-size-related index N which reflect flow patterns have been characterized by using Zuber & Findlay Drift–Flux Model. The calculation of C k indicates that the instabilities of C k correspond to the transitional flow pattern of oil/water two-phase flow, which gives a new criterion that transitional flow pattern falls into the water hold-up ( Y w ) range of 0.2 Y w