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Published on: May 9, 2021
Lattice-Boltzmann method for simulating spherical bubbles with no tangential stress boundary conditions
Xiaolong Yin1, Donald L Koch, Rolf Verberg
1School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.
Summary
A new lattice-Boltzmann boundary rule accurately simulates bubbly flows by enabling slip at liquid-gas interfaces. This method is robust for steady and unsteady flows of spherical bubbles within a low Reynolds number range.
Area of Science:
- Computational Fluid Dynamics
- Multiphase Flow Simulation
- Mesoscopic Physics
Background:
- Simulating fluid interfaces, particularly liquid-gas interfaces, presents challenges in computational fluid dynamics.
- Accurate representation of boundary conditions, such as slip, is crucial for modeling phenomena like bubbly flows.
- Existing lattice-Boltzmann models often require complex multi-component approaches for such simulations.
Purpose of the Study:
- To develop a novel lattice-Boltzmann boundary rule to implement slip boundary conditions at liquid-gas interfaces.
- To enable the simulation of bubbly flows using a simplified single-component lattice-Boltzmann model.
- To validate the accuracy and robustness of the developed method for specific flow regimes.
Main Methods:
- Development of a specific lattice-Boltzmann boundary rule designed to recover slip conditions.
- Application of this rule within a single-component lattice-Boltzmann model framework.
- Numerical simulation of steady and unsteady flows around spherical bubbles.
Main Results:
- The developed boundary rule successfully recovers the slip boundary condition at the liquid-gas interface.
- The single-component lattice-Boltzmann model with the new rule accurately simulates bubbly flows with nearly spherical, non-coalescing bubbles.
- Numerical tests confirm the method's robustness and accuracy for Reynolds numbers ranging from 0 to 30.
Conclusions:
- The proposed lattice-Boltzmann boundary rule offers an efficient and accurate approach for simulating bubbly flows.
- This method simplifies the simulation of multiphase flows by allowing the use of single-component models.
- The technique is validated for low Reynolds number flows, demonstrating its potential for various applications.
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