Research on performance of dual-inlet gas-liquid cylindrical cyclone based on liquid film flow pattern

Gas-liquid cylindrical cyclone (GLCC) is a separation device coupling with centrifugal force and gravity, and is often used for deep-sea oil and gas separation. Liquid carry-over (LCO) in the gas phase is a key issue affecting the application of GLCC. Previous studies have pointed out that the percent-LCO is closely related to the liquid film flow pattern in the upper cylinder, so it is reasonable to control the percent-LCO by controlling the liquid film flow pattern. This paper proposes a dual-inlet gas-liquid cyclone separator with an upward-branch inlet, and a valve is added to the upward-branch inlet. The flow ratio between the primary and secondary inlets is controlled to change the liquid film flow pattern of the upper cylinder. Using the high-speed camera, the spatial distribution characteristics of the liquid film are systematically studied by changing the inlet gas-liquid flow-rate and valve opening. And through the numerical simulation, the GLCC liquid film flow pattern, internal streamline and velocity characteristics are analyzed. When the flow area ratio of the secondary path of the inclined pipe is changed from 100% to 0, the flow rate through the primary inlet increases, and the distribution height of the liquid film along the upper cylinder decreases. The liquid film is concentrated near the primary entrance to form swirling flow. Simulation results show that, in the previously described procedure, the center of the swirling vortex core gradually stabilizes, which is beneficial to inhibit the LCO. Adjusting the opening of valve to control the flow pattern of the liquid film is a feasible method to improve the separation performance of GLCC. © 2022, Editorial Board of CIESC Journal. All right reserved.