Effect of Riser Base and Flowline Gas Injection on the Characteristics of Gas-Liquid Two-Phase Flow in a Vertical Riser System

We report an experimental study has been conducted on a 52 mm internal diameter vertical riser of which is met at the riser base by a 10.5 m long. The effect of two different gas inlet configurations were tested: riser base gas injection and horizontal inline injection 40 meters upstream of the riser base. A 16×16 wire-mesh sensor was used to measure the void fraction at the riser top and we present a detailed analysis of the characteristics of flow because of the injection scheme. These include regimes and cross-sectional void fraction distributions of the time series data. Among our findings are wall-peaking gas fraction profiles at lower gas injection rates through the flowline, while core-peaking profiles were established at the same flow conditions for riser base injection. This provides valuable information that can feed into the design of downstream facilities such as slug catchers and separators.