Simulating the spreading of a drop in the terraced wetting regime

For atomic fluids, droplet spreading in the terraced wetting regime is investigated using molecular dynamics. The radii of the terraced layers vary as root t regardless of system size, lattice geometry, and thermostating, in agreement with experimental data. Previous simulations are shown to disagree due to porosity of the lattice. The spreading proceeds initially via downward mass transfer in the outer regions of the drop. When layers close to the solid surface become impenetrable, mass transfer occurs only at the drop edges, as suggested by de Gennes and Cazabat.