Currently, the fluid drop impact on solid walls is an important research area in the scientific community. The droplet spreads out on the wall after impact. In some cases, the tip of the spreading lamella levitates and travels along the surface without touching the wall. Quite interestingly, this is observed in drop impact on both hydrophobic and hydrophilic surfaces. What are the main reasons for this phenomena? How can we categorize them?
The image is from Article Drop Impact on a Solid Surface