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EPTT 2024
14th Spring School on Transition and Turbulence
TURBULENCE CHARACTERISTICS ANALYSIS IN HORIZONTAL OIL-WATER CORE-ANNULAR FLOW VIA PARTICLE IMAGE VELOCIMETRY (PIV).
Submission Author:
Jorge enrique Arrollo Caballero , SP
Co-Authors:
Jorge enrique Arrollo Caballero, Pedro José Miranda Lugo, Oscar Mauricio Hernandez Rodriguez
Presenter: Oscar Mauricio Hernandez Rodriguez
doi://10.26678/ABCM.EPTT2024.EPT24-0042
Abstract
The oil-water core-annular flow pattern is characterized by the configuration in which the more viscous fluid occupies the core of the pipe, and the less viscous fluid forms a ring around the core, maintaining contact with the pipe wall. It has been suggested as a means of transporting or artificially lifting high-viscous oils since it minimizes frictional pressure drop. Previous studies have shown that the transition and stability phenomena of the core-annular flow pattern could be associated with the interfacial wave structure and the phases’ turbulence. However, the information available in the literature on wave amplitude, wavelength, and turbulence statistics is limited, especially for liquid-liquid systems. This study aims to characterize the hydrodynamic behavior of the core-annular flow, obtaining the axial and radial velocity distributions, as well as its turbulent characteristics, such as U_rms, V_rms, and Reynolds stress. Experiments were carried out in a borosilicate glass tube with an internal diameter of 9.7 mm using the PIV technique. The PIV methodology allowed to obtain the detailed hydrodynamics of the core-annular flow by acquiring 3000 frames in the pipe's diametral plane, and the interface's height using the PLIF technique. A noticeable change in the axial velocity profile was observed near the interface at the top of the tube, suggesting a possible instable hydrodynamic condition. In addition, the increase in mixture velocity directly impacted the magnitude of U_rms and V_rms, reflecting an increase in turbulence in the flow. The Reynolds stresses were examined under different experimental conditions, revealing a characteristic behavior of the annular flow pattern in the turbulent shear stress data, especially at the interface region at the top of the tube.
Keywords
Core-annular flow, oil-water flow, PIV, Turbulence statistic, Velocity profiles.
