Molecular dynamics simulation on dynamic behaviors of nanodroplets impinging on solid surfaces decorated with nanopillars

Droplets’ impinging on a solid surface is common phenomenon in industry and agriculture. With the development of micro nano technology, quantitative descriptions behaviors for nanodroplets are expected to be further explored. Molecular dynamics (MD) simulation adopted investigate water cooper surfaces which have been decorated with square nanopillars. The dynamical characteristics analyzed at 5 different pillar heights, 6 characteristic energy values, wide range droplet velocities. results show that there no obvious difference among nanodroplets, whose radii from 35 45 Å, surface. increase velocity, wetting pattern steady first transfers Cassie state (<i>V</i><sub>0</sub> = 2–3 Å/ps) Wenzel 4–10 Å/ps), then it returns 11–13 again. Nanodroplets bounce off when <i>V</i><sub>0</sub> > 13 Å/ps. relationship between maximum spreading time velocity presented. Inflection points curve discovered their formation mechanism studied. factors states lower than 9 Å/ps nearly same; however, they decrease gradually higher In addition, increasing height nanopillars facilitates transition reduces radius nanodroplets. mechanism, yields impinge nanopillars, investigated. stage, almost identical. influence nanopillar mainly plays role retraction stage droplets fades away as increases. Moreover, benefits time. Especially, do not experience kept until reach stable increased 0.714 kcal/mol. Compared factor, centroid nanodroplet very sensitive change energy.