Local measurements and computational fluid dynamics simulations in a gas-liquid cylindrical cyclone separator.

摘要

The Gas Liquid Cylindrical Cyclone (GLCC©) separator is an attractive compact separator alternative to the conventional vessel-type separator. Local measurements and Computational Fluid Dynamics (CFD) simulations in GLCC© separators are scarce. The main objective of this study is to conduct local measurements and CFD simulations to aid in the understanding of the swirling flow inside the GLCC. Another objective is to gather data to develop correlations to predict axial and tangential velocities inside the GLCC to aid in mechanistic model development for the GLCC©.; The behavior of small gas bubbles in the lower part of the GLCC ©, below the inlet, and the related gas carry-under phenomena is also investigated. This investigation was performed by utilizing a commercially available computational fluid dynamics (CFD) code. Simulations of single-phase and two-phase flows were carried out and bubble trajectories were obtained in an axisymmetric geometry that represents the GLCC© configuration. The effect of the free interface that forms between the gas and liquid phases on the velocity profiles was examined. The bubble trajectory analysis was used to quantify the effects of the important parameters on bubble carry-under. These include bubble size, ratio of the GLCC© length below the inlet to diameter, viscosity, Reynolds number, and inlet tangential velocity.; Local measurements were conducted. Axial and tangential velocities and turbulent intensities across the GLCC© diameter were measured at 24 different axial locations (12.5&inches; to 35.4&inches; below the inlet) by using a Laser Doppler Velocimeter (LDV). Measurements are conducted for different inlet configurations and inlet-outlet orientations. The measurements were conducted for a wide range of Reynolds numbers of about 1500 to 67,000. Measurements were conducted with water at liquid flow rates of 72, 30 and 10 gpm. Also, high viscosity measurements are conducted for flow rates of 54 gpm (70), 30 gpm (70), and 10 gpm (70). Measurements are used to create color contour plots of axial and tangential velocity and turbulent kinetic energy. Additionally, 3-D CFD simulations with different turbulence models are conducted. Simulations results are compared to LDV measurements.; Local LDV measurements are used to develop a new correlation for vortex center wavelength and to improve existing correlations for swirl intensity, axial and tangential velocities. A framework is suggested that shows how sophisticated 3-D correlations can be developed to predict complex swirling flow in the GLCC©.