Laser-driven droplet deformation at low Weber numbers
Abstract
We investigate droplet deformation following laser-pulse impact at low Weber numbers (We ~ 0.1-100). Droplet dynamics can be characterized by two key parameters: the impact We number and the width, W, of the distribution of the impact force over the droplet surface. By varying laser pulse energy, our experiments traverse a phase space comprising (I) droplet oscillation, (II) breakup, or (III) sheet formation. Numerical simulations complement the experiments by determining the pressure width and by allowing We and W to be varied independently, despite their correlation in the experiments. A single phase diagram, integrating observations from both experiments and simulations, demonstrates that all phenomena can be explained by a single parameter: the deformation Weber number Wed=f(We, W) that is based on the initial radial expansion speed of the droplet, following impact. The resulting phase diagram separates (I) droplet oscillation for Wed<5, from (II) breakup for 5<Wed<60, and (III) sheet formation for Wed>60.
Cite
@article{arxiv.2509.01495,
title = {Laser-driven droplet deformation at low Weber numbers},
author = {M. Kharbedia and H. L. França and H. K. Schubert and D. J. Engels and M. Jalaal and O. O. Versolato},
journal= {arXiv preprint arXiv:2509.01495},
year = {2025}
}