Proportional scaling molecular dynamics simulations of the wetting experiments of water droplets on ink-patterned printing paper

In experiments, printing paper is imprinted with three different ink micropatterns (square, grid, and stripe). The wetting contact angle of water droplets on a heterogeneous surface is then investigated using a proportionate scaling molecular dynamics (MD) simulation, where the water droplets and the ink-patterned printing paper are both shrunk by a factor of 200 000 collectively. The errors from the theoretical values are always less than 1°, which is much less than the bias of experimental measurement data, according to the modeling contact angles. It has been demonstrated that this proportionate scaling approach works well to appropriately explain the interaction between micro-/nanostructures and liquids.