Numerical simulation on wettability of hydrophobic surfaces based on lattice boltzmann method

Wettability has an important influence on the dynamic behavior of liquid on a solid surface. The special wettability is the fundamental reason that hydrophobic surfaces are widely applied in drag reduction, noise reduction, antifouling and so on. In this paper, the wettability of hydrophobic surfaces is simulated by lattice Boltzmann method based on Shan-Chen model, and effect of the material property and microcosmic topography on wettability of hydrophobic surfaces is obtained. The simulation results show that in order to make hydrophobic surfaces under Cassie-Baxter wetting state, the height of microcosmic topography must be greater than a critical value. Once hydrophobic surfaces are under Cassie-Baxter wetting state, increasing the height of microcosmic topography does not improve its hydrophobicity. The apparent contact angle of hydrophobic surfaces first increases and then decreases when the gas-liquid interface fraction increases, and there is an optimum gas-liquid interface fraction so that the apparent contact angle is maximized.