Wouter Mostert

Understanding the impact of a single drop onto a surface is difficult enough, but in many applications, such impacts are not isolated, and complex effects involving interactions between neighbouring or successive droplet impacts need to be considered. This talk will discuss perhaps the simplest case, of the simultaneous  impact of two neighbouring droplets, which has the striking result that their interaction produces a vertically projecting lamella. Numerical simulations of the process, from the Basilisk library, will be presented; the simulations are compared with experiment, and the detailed kinematics and energetics of the process are inspected, culminating in an energetic model for the vertical lamella. The talk will conclude with a discussion on related questions, such as the rather low splashing threshold, and the vast array of variations and generalisations on the problem that are becoming more feasible in numerical modelling.

Wouter Mostert is one of the pillars of the Basilisk community, having orgainzed the Basilisk and Gerris User Meeting in Oxford in July 2025.