In this talk, we will first present a thermodynamically consistent and conservative diffuse-interface model for gas-liquid-solid three-phase flows where a novel free energy is proposed for the gas-liquid-solid three-phase flows. Furthermore, a smooth indicator function of the solid phase is also introduced in the consistent Navier-Stokes equations to preserve the velocity boundary condition on the solid surface. Based on the developed diffuse-interface model, the fluid interface dynamics, the fluid-structure interaction, and the wetting property of the solid surface can be described simply and efficiently. Additionally, the total energy is also shown to be dissipative for the two-phase flows in the stationary geometries. To test the present diffuse-interface model, we then develop a consistent and conservative lattice Boltzmann method and conduct some simulations. The numerical results also confirm the energy dissipation and good capability of the proposed diffuse-interface model in the study of two-phase flows in complex geometries and gas-liquid-particle flows.
 

lattice Boltzmann method,phase-field model,multiphase flows