  Single component pseudo-potential lattice Boltzmann model has been widely
applied in multiphase simulation due to its simplicity and stability. In many
research, it has been claimed that this model can be stable for density ratios
larger than 1000, however, the application of the model is still limited to
small density ratios when the contact angle is considered. The reason is that
the original contact angle adjustment method influences the stability of the
model. Moreover, simulation results in present work show that, by applying the
contact angle adjustment method, the density distribution near the wall is
artificially changed, and the contact angle is dependent on the surface
tension. Hence, it is very inconvenient to apply this method with a fixed
contact angle, and the accuracy of the model cannot be guaranteed. To solve
these problems, a contact angle adjustment method based on the geometry
analysis is proposed and numerically compared with the original method.
Simulation results show that, with the new contact angle adjustment method, the
stability of the model is highly improved when the density ratio is relatively
large, and it is independent of the surface tension.
