### Abstract

Language | English |
---|---|

Journal | Journal of Computational Physics |

Early online date | 6 Oct 2016 |

DOIs | |

Publication status | E-pub ahead of print - 6 Oct 2016 |

### Fingerprint

### Keywords

- lattice Boltzmann method
- axisymmetric flow
- color-gradient model
- high viscosity ratio
- Rayleigh instability
- collision operator
- single-component collision operator
- perturbation operator
- recolouring operator
- interfacial tension
- binary fluids
- high-viscosity ratio
- multiple-relaxation model

### Cite this

*Journal of Computational Physics*. https://doi.org/10.1016/j.jcp.2016.10.007

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**A lattice Boltzmann method for axisymmetric multicomponent flows with high viscosity ratio.** / Liu, Haihu; Wu, Lei; Ba, Yan; Xi, Guang; Zhang, Yonghao.

Research output: Contribution to journal › Article

TY - JOUR

T1 - A lattice Boltzmann method for axisymmetric multicomponent flows with high viscosity ratio

AU - Liu, Haihu

AU - Wu, Lei

AU - Ba, Yan

AU - Xi, Guang

AU - Zhang, Yonghao

PY - 2016/10/6

Y1 - 2016/10/6

N2 - A color-gradient lattice Boltzmann method (LBM) is proposed to simulate ax- isymmetric multicomponent flows. This method uses a collision operator that is a combination of three separate parts, namely single-component collision op- erator, perturbation operator, and recoloring operator. A source term is added into the single-component collision operator such that in each single-component region the axisymmetric continuity and momentum equations can be exactly re- covered. The interfacial tension effect is realized by the perturbation operator, in which an interfacial force of axisymmetric form is derived using the concept of continuum surface force. A recoloring operator proposed by Latva-Kokko and Rothman is extended to the axisymmetric case for phase segregation and maintenance of the interface. To enhance the method’s numerical stability for handling binary fluids with high viscosity ratio, a multiple-relaxation-time mod- el is used for the collision operator. Several numerical examples, including static droplet test, oscillation of a viscous droplet, and breakup of a liquid thread, are presented to test the capability and accuracy of the proposed color-gradient LB- M. It is found that the present method is able to accurately capture the phase interface and produce low spurious velocities. Also, the LBM results are all in good agreement with the analytical solutions and/or available experimental data for a very broad range of viscosity ratios.

AB - A color-gradient lattice Boltzmann method (LBM) is proposed to simulate ax- isymmetric multicomponent flows. This method uses a collision operator that is a combination of three separate parts, namely single-component collision op- erator, perturbation operator, and recoloring operator. A source term is added into the single-component collision operator such that in each single-component region the axisymmetric continuity and momentum equations can be exactly re- covered. The interfacial tension effect is realized by the perturbation operator, in which an interfacial force of axisymmetric form is derived using the concept of continuum surface force. A recoloring operator proposed by Latva-Kokko and Rothman is extended to the axisymmetric case for phase segregation and maintenance of the interface. To enhance the method’s numerical stability for handling binary fluids with high viscosity ratio, a multiple-relaxation-time mod- el is used for the collision operator. Several numerical examples, including static droplet test, oscillation of a viscous droplet, and breakup of a liquid thread, are presented to test the capability and accuracy of the proposed color-gradient LB- M. It is found that the present method is able to accurately capture the phase interface and produce low spurious velocities. Also, the LBM results are all in good agreement with the analytical solutions and/or available experimental data for a very broad range of viscosity ratios.

KW - lattice Boltzmann method

KW - axisymmetric flow

KW - color-gradient model

KW - high viscosity ratio

KW - Rayleigh instability

KW - collision operator

KW - single-component collision operator

KW - perturbation operator

KW - recolouring operator

KW - interfacial tension

KW - binary fluids

KW - high-viscosity ratio

KW - multiple-relaxation model

UR - http://www.sciencedirect.com/science/journal/00219991

U2 - 10.1016/j.jcp.2016.10.007

DO - 10.1016/j.jcp.2016.10.007

M3 - Article

JO - Journal of Computational Physics

T2 - Journal of Computational Physics

JF - Journal of Computational Physics

SN - 0021-9991

ER -