Effects of pressure control on droplet size distribution and flow regimes in gas-liquid cylindrical cyclone

Marine production platforms and subsea production systems desperately need compact and highly efficient gas-liquid separators. The gas-liquid cylindrical cyclone (GLCC), which mainly utilizes gravitational and centrifugal forces to achieve separation, can be an superior choice. Herein, a pressure control scheme is proposed that allows the GLCC to realize fast and stable gas-liquid separation. The droplet size distributions measured by a Malvern RTSizer indicated that increasing the liquid superficial velocity only increased the distribution of small droplets at the inlet. The droplet size distribution of the down sampling at a high dimensionless pressure was larger than that at a low dimensionless pressure, which can be explained by the droplet migration model. As the dimensionless pressure decreased, four flow regimes were experimentally observed: annular flow, churn flow stratified flow, falling droplets, and pure gas. Electrical resistance tomography measurement results indicated that better convergence of the bubbly filament was achieved at a higher dimensionless pressure