Articles producció científica> Enginyeria Mecànica

Transient large-scale two-phase flow structures in a 3D bubble column reactor

  • Datos identificativos

    Identificador: imarina:6300690
    Autores:
    Fard, Mojtaba GorakiVernet, AntonStiriba, YoussefGrau, Xavier
    Resumen:
    This paper analyses the local and time-dependent behavior of large-scale structures responsible for liquid circulation in gas-water flow of a 3-D cylindrical bubble column of high aspect ratio with a multiple orifice for uniform aeration. The large-scale flow structures play an important role in the mixing and the mass transfer while coherent structures dominate hydrodynamic characteristics of the turbulent flow field. A three-dimensional Euler-Euler large eddy simulation (LES) model was used to calculate large-scale structures and their interaction with bubbles at inlet superficial gas velocities of U-G = 6 and 8.4 cm/s where vortical-spiral and turbulent flow regimes occur. The two-phase model gives good agreements with experimental measurements. We use a conditional sampling procedure of liquid velocity and gas hold-up time series to identify and educe the development of coherent flow structures which consists in a pair of counter-rotating vortices convected in a staggered pattern along the column in both the vortical-spiral and central plume regions. On average, the detected instantaneous events for each template account for about 12-15% of the data recorded and may appear simultaneously. These events produce important fluctuations in the axial liquid velocity and gas void fraction. The sampling procedure yielded the averaged topology of the three-dimensional large-scale structures which was visualized using isosurfaces of the vorticity for different gas flow rates. The structures have spiral tube-shaped topology rotating along the column near the walls with a pair of counter-rotating cells sustained through the flow. This work provides deep insights into turbulent flow field in gas-liquid bubble column by LES and pattern recognition. (C) 2020 Published by Elsevier
  • Otros:

    Autor según el artículo: Fard, Mojtaba Goraki; Vernet, Anton; Stiriba, Youssef; Grau, Xavier
    Departamento: Enginyeria Mecànica
    Autor/es de la URV: Grau Vidal, Francesc Xavier / Stiriba, Youssef / Vernet Peña, Antonio
    Palabras clave: Vortex Turbulence Regime transitions Numerical-simulation Model Liquid velocity Large-scale structures Large-eddy-simulation Large-eddy simulation Gas-distribution Dynamics Conditional sampling Cfd simulation Bubble column reactor Behavior
    Resumen: This paper analyses the local and time-dependent behavior of large-scale structures responsible for liquid circulation in gas-water flow of a 3-D cylindrical bubble column of high aspect ratio with a multiple orifice for uniform aeration. The large-scale flow structures play an important role in the mixing and the mass transfer while coherent structures dominate hydrodynamic characteristics of the turbulent flow field. A three-dimensional Euler-Euler large eddy simulation (LES) model was used to calculate large-scale structures and their interaction with bubbles at inlet superficial gas velocities of U-G = 6 and 8.4 cm/s where vortical-spiral and turbulent flow regimes occur. The two-phase model gives good agreements with experimental measurements. We use a conditional sampling procedure of liquid velocity and gas hold-up time series to identify and educe the development of coherent flow structures which consists in a pair of counter-rotating vortices convected in a staggered pattern along the column in both the vortical-spiral and central plume regions. On average, the detected instantaneous events for each template account for about 12-15% of the data recorded and may appear simultaneously. These events produce important fluctuations in the axial liquid velocity and gas void fraction. The sampling procedure yielded the averaged topology of the three-dimensional large-scale structures which was visualized using isosurfaces of the vorticity for different gas flow rates. The structures have spiral tube-shaped topology rotating along the column near the walls with a pair of counter-rotating cells sustained through the flow. This work provides deep insights into turbulent flow field in gas-liquid bubble column by LES and pattern recognition. (C) 2020 Published by Elsevier Ltd.
    Áreas temáticas: Physics and astronomy (miscellaneous) Physics and astronomy (all) Mechanics Mechanical engineering Matemática / probabilidade e estatística General physics and astronomy Fluid flow and transfer processes Engenharias iv Engenharias iii Engenharias ii Ciência de alimentos Ciência da computação Biodiversidade
    Acceso a la licencia de uso: https://creativecommons.org/licenses/by/3.0/es/
    ISSN: 03019322
    Direcció de correo del autor: youssef.stiriba@urv.cat anton.vernet@urv.cat francescxavier.grau@urv.cat
    Identificador del autor: 0000-0002-0272-7807 0000-0002-7028-1368 0000-0002-4077-7338
    Fecha de alta del registro: 2024-10-12
    Versión del articulo depositado: info:eu-repo/semantics/acceptedVersion
    Enlace a la fuente original: https://www.sciencedirect.com/science/article/abs/pii/S0301932219306196
    URL Documento de licencia: https://repositori.urv.cat/ca/proteccio-de-dades/
    Referencia al articulo segun fuente origial: International Journal Of Multiphase Flow. 127 (UNSP 103236): 103236-
    Referencia de l'ítem segons les normes APA: Fard, Mojtaba Goraki; Vernet, Anton; Stiriba, Youssef; Grau, Xavier (2020). Transient large-scale two-phase flow structures in a 3D bubble column reactor. International Journal Of Multiphase Flow, 127(UNSP 103236), 103236-. DOI: 10.1016/j.ijmultiphaseflow.2020.103236
    DOI del artículo: 10.1016/j.ijmultiphaseflow.2020.103236
    Entidad: Universitat Rovira i Virgili
    Año de publicación de la revista: 2020
    Tipo de publicación: Journal Publications
  • Palabras clave:

    Fluid Flow and Transfer Processes,Mechanical Engineering,Mechanics,Physics and Astronomy (Miscellaneous)
    Vortex
    Turbulence
    Regime transitions
    Numerical-simulation
    Model
    Liquid velocity
    Large-scale structures
    Large-eddy-simulation
    Large-eddy simulation
    Gas-distribution
    Dynamics
    Conditional sampling
    Cfd simulation
    Bubble column reactor
    Behavior
    Physics and astronomy (miscellaneous)
    Physics and astronomy (all)
    Mechanics
    Mechanical engineering
    Matemática / probabilidade e estatística
    General physics and astronomy
    Fluid flow and transfer processes
    Engenharias iv
    Engenharias iii
    Engenharias ii
    Ciência de alimentos
    Ciência da computação
    Biodiversidade
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