  We use the conservative phase-field lattice Boltzmann method to investigate
the dynamics when a Newtonian droplet comes in contact with an immiscible
viscoelastic liquid film. The dynamics of the three liquid phases are explored
through numerical simulations, with a focus on illustrating the contact line
dynamics and the viscoelastic effects described by the Oldroyd-B model. The
droplet dynamics are contrasted with the case of a Newtonian fluid film. The
simulations demonstrate that when the film is viscoelastic, the droplet
dynamics become insensitive to the film thickness when the polymer viscosity
and relaxation time are large. A viscoelastic ridge forms at the moving contact
line, which evolves with a power-law dependence on time. By rescaling the
interface profile of the ridge using its height and width, it appears to
collapse onto a similar shape. Our findings reveal a strong correlation between
the viscoelastic stress and the interface shape near the contact line.
