Simulation of contact line dynamics in a two-dimensional capillary tube bythe lattice Boltzmann model - art. no. 051603

During immiscible-fluid displacement, the contact angle between the interfa ce and the wall of a tube, as well as the velocity V of the contact line wh ere a fluid interface intersects the wall of a tube, depends on the applied capillary pressure P-cap. In this paper, the contact line dynamics of immi scible-fluid displacement is simulated by using the lattice Boltzmann model in a two-dimensional capillary channel with an ideally smooth wall. The V dependence of the contact angle is studied for two different wetting cases. Our simulational results are in good agreement with those based on theoret ical computations and with molecular dynamics simulations. Tn particular, t he power-law behavior P(cap)similar toV(tau) is found with an exponent x ve ry close to 1. The simulations suggest that the lattice Boltzmann model may serve as an alternative reliable quantitative approach to study the contac t line dynamics, and also may be a promising tool for invesitgating some ot her immiscible displacement related subjects.