Pseudopotential lattice Boltzmann equation method for two-phase flow: A higher-order Chapmann-Enskog expansion
Qinglan Zhai1, Lin Zheng2, Song Zheng3
1School of Economics Management and Law, Chaohu University, Chaohu 238000, People's Republic of China.
Physical Review. E
|March 17, 2017
Summary
This study analyzes third-order error terms in the pseudopotential lattice Boltzmann equation (LBE) for fluid dynamics. Modifications ensure thermodynamic consistency, with simulations confirming accurate predictions.
Area of Science:
- Fluid Dynamics
- Computational Physics
- Thermodynamics
Background:
- The pseudopotential lattice Boltzmann equation (LBE) is a powerful tool for simulating fluid dynamics.
- Higher-order error terms in LBE can affect the accuracy of pressure tensor calculations.
- Ensuring thermodynamic consistency is crucial for the validity of LBE models.
Purpose of the Study:
- To analyze the contribution of third-order error terms to the pressure tensor in the pseudopotential LBE.
- To modify the LBE to ensure consistency with thermodynamic theory.
- To validate the modified LBE through numerical simulations.
Main Methods:
- Application of a higher-order Chapmann-Enskog expansion technique to the pseudopotential LBE.
- Introduction of a force term to modify pressure tensor coefficients for thermodynamic consistency.
- Numerical simulations to verify the accuracy of the modified LBE.
Main Results:
- Detailed analysis of third-order error term contributions to the pressure tensor.
- Demonstration that the modified LBE coefficients align with thermodynamic principles.
- Numerical results show excellent agreement between the modified LBE predictions and analytical solutions.
Conclusions:
- The higher-order Chapmann-Enskog expansion effectively analyzes error terms in pseudopotential LBE.
- The introduced force term successfully reconciles LBE with thermodynamic theory.
- The validated LBE provides accurate predictions for fluid dynamics simulations.
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