# Numerical Simulation Study of the Effect of Outlet on the Axial Vortex Separator

Document Type : Regular Article

Authors

1 Hubei Key Laboratory of Petroleum Drilling and Production Engineering, Wuhan, Hubei, 430100, China

2 Laboratory of Multiphase Pipe Flow, Gas Lift Innovation Center, China National Petroleum Corp, Yangtze University, Wuhan, Hubei, 430100, China

10.47176/jafm.17.9.2461

Abstract

This study utilizes numerical simulations and dimensional analysis to investigate the impact of the two-phase outlet on flow field characteristics and separation efficiency of the separator. The study revealed a boundary layer separation at the water outlet, which was subsequently addressed to reduce energy losses in the separator. Dimensional analysis considered the influences of operational, structural, and physical parameters on the separator's performance. With other structural parameters held constant, separation efficiency is directly proportional to the ratio of inlet and oil-outlet diameter. Additionally, the separation efficiency is also associated with Re and the ratio of the inlet to the water-outlet diameter. When the diameter of the water outlet is constant, the axial vortex separator achieves optimal separation when the ratio of inlet and water-outlet diameter is 0.563, with a maximum separation efficiency of 97.00%. The optimal separation efficiency is reached at Re=22,908 under various operational conditions. Separation efficiency increases with water content, peaking at an inlet water content of 0.9 across different structural parameters. Separation efficiency shows an increase followed by a decrease with the rise in inlet flow rate(vi), achieving the best performance at vi=3m/s for the different separator structures studied.

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Main Subjects

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