Contact angle adjustment in equation-of-state-based pseudopotential model.

Area of Science:

• Computational physics
• Fluid dynamics
• Numerical methods

Background:

• The single component pseudopotential lattice Boltzmann model (LBM) is widely used for multiphase simulations due to its stability and simplicity.
• Existing LBM applications are limited by contact angle considerations, especially at high density ratios.
• The original contact angle adjustment method compromises model stability and accuracy, introducing artificial density changes and surface tension dependence.

Purpose of the Study:

• To address the limitations of the original contact angle adjustment method in LBM simulations.
• To develop and validate a novel contact angle adjustment method based on geometric analysis.
• To enhance the stability and accuracy of LBM for multiphase flows with large density ratios and specified contact angles.

Main Methods:

• Implementation of a single component pseudopotential lattice Boltzmann model.
• Development of a new contact angle adjustment method utilizing geometric analysis.
• Numerical comparison of the proposed method against the original contact angle adjustment technique.

Main Results:

• The proposed geometric analysis method significantly improves LBM stability for large density ratios.
• The new method eliminates the artificial alteration of density distribution near the wall.
• The contact angle adjustment becomes independent of surface tension, enhancing applicability.
• The model's accuracy is better guaranteed with the proposed method.

Conclusions:

• The geometric analysis-based contact angle adjustment method overcomes the limitations of the original approach.
• This advancement enables more reliable and accurate multiphase LBM simulations at high density ratios.
• The method offers greater convenience for applications requiring fixed contact angles, independent of surface tension effects.