title: Wetting condition in diffuse interface simulations of contact line motion.
abstract: We investigate the wetting condition for diffuse-interface methods in the simulation of two-fluid flows with moving contact lines. A current method, which uses a surface-energy approach, is shown not to result in a slope of the interface that is consistent with the prescribed value of the contact angle. A geometric formulation is proposed that does result in the prescribed contact angle. Test results are presented for the axisymmetric droplet spreading due to the capillary force and the motion of a droplet on a solid substrate in a shear flow.
authors.affiliation: Department of Chemical Engineering, Imperial College London, SW7 2AZ, United Kingdom.
authors.forename: Hang
authors.initials: H
authors.lastname: Ding
authors.forename: Peter D M
authors.initials: PD
authors.lastname: Spelt