  This paper proposes a new strategy to implement the free-energy based wetting
boundary condition within the phase-field lattice Boltzmann method. The
greatest advantage of the proposed method is that the implementation of contact
line motion can be significantly simplified while still maintaining good
accuracy. For this purpose, the liquid-solid free energy is treated as a part
of the chemical potential instead of the boundary condition, thus avoiding
complicated interpolations with irregular geometries. Several numerical testing
cases including the droplet spreading processes on the idea flat, inclined and
curved boundaries are conducted, and the results demonstrate that the proposed
method has good ability and satisfactory accuracy to simulate contact line
motions.
