Doctoral Thesis
DOI
10.11606/T.18.2016.tde-30052016-160240
Document
Author
Full name
Ricardo Pereira de Avila
Institute/School/College
Knowledge Area
Date of Defense
Published
São Carlos, 2016
Supervisor
Committee
Rodriguez, Oscar Maurício Hernandez (President)
Aguiar, Fernando Guimarães
Seleghim Junior, Paulo
Souza, Leandro Franco de
Wendland, Edson Cezar
Title in Portuguese
Estudo fenomenológico e numérico do escoamento estratificado óleo-água ondulado e com mistura na interface
Keywords in Portuguese
CFD
Dispersão de gotículas
Escoamento bifásico
Escoamento óleo-água
Fator de entranhamento
Modelagem matemática unidimensional
Onda interfacial
Queda de pressão
Abstract in Portuguese
Title in English
Phenomenological and numerical study of wavy stratified oil-water pipe flow with interfacial mixing
Keywords in English
CFD
Droplet dispersion
Entrainment factor
Interfacial wave
Oil-water flow
One-dimensional mathematical modeling
Pressure drop
Stratified flow
Two-phase flow
Abstract in English
Two-phase flows are present in many natural and industrial processes, such as in the oil industry. They may be found arranged in several flow patterns, including the wavy stratified flow and the stratified with mixing at the interface. The stratified oil-water flow has been used as a convenient way to avoid the formation of emulsions of water in oil and have a common occurrence in directional oil wells. When the interfacial wave exceeds a certain geometric and kinematic limit the phenomenon of drop entrainment arises at the interface, causing an increase of pressure drop. Models have been presented in the literature in an attempt to describe the phenomenon of drop entrainment. In this work, we present a new method for the one-dimensional mathematical modeling of entrainment in order to improve the prediction of oil volume fraction and pressure drop. It was also used a commercial computational fluid dynamics tool (CFD) to obtain the values of flow parameters of wavy stratified oil-water flow, such as oil volume fraction, pressure drop, amplitude and length of the interfacial waves. The results of the phenomenological modeling for entrainment and CFD were compared with experimental databases. The CFD results are in agreement with the experimental results in both the qualitative analysis of the geometric properties of the interfacial waves and in direct comparison with oil-volumetric-fraction and pressure-drop data. The numerical results of the phenomenological model for entrainment factors are in agreement with data from the literature.